diff --git a/src/admin/base.css b/src/admin/base.css
index 17081f6..f9724d5 100644
--- a/src/admin/base.css
+++ b/src/admin/base.css
@@ -412,4 +412,9 @@ img {
     transition-duration: 0.01ms !important;
     scroll-behavior: auto !important;
   }
+
+  .admin-spinner {
+    animation-duration: 0.8s !important;
+    animation-iteration-count: infinite !important;
+  }
 }
diff --git a/src/admin/pages/Attendance.tsx b/src/admin/pages/Attendance.tsx
index 81d6b28..8f2c514 100644
--- a/src/admin/pages/Attendance.tsx
+++ b/src/admin/pages/Attendance.tsx
@@ -576,10 +576,7 @@ export default function Attendance() {
                     <div className="attendance-project-header">
                       <span className="attendance-shift-label">Projekt</span>
                       {activeProjectId ? (
-                        <span
-                          className="admin-badge admin-badge-wrap"
-                          style={{ fontSize: "0.8125rem" }}
-                        >
+                        <span className="admin-badge admin-badge-wrap text-sm">
                           {projects.find(
                             (p) => String(p.id) === String(activeProjectId),
                           )
@@ -587,12 +584,7 @@ export default function Attendance() {
                             : `Projekt #${activeProjectId}`}
                         </span>
                       ) : (
-                        <span
-                          className="text-muted"
-                          style={{ fontSize: "0.8125rem" }}
-                        >
-                          Žádný
-                        </span>
+                        <span className="text-muted text-sm">Žádný</span>
                       )}
                     </div>
                     <select
@@ -601,8 +593,7 @@ export default function Attendance() {
                         handleSwitchProject(e.target.value || null)
                       }
                       disabled={switchingProject}
-                      className="admin-form-select"
-                      style={{ fontSize: "0.875rem" }}
+                      className="admin-form-select text-md"
                     >
                       <option value="">— Bez projektu —</option>
                       {projects.map((p) => (
@@ -654,8 +645,7 @@ export default function Attendance() {
                     <button
                       onClick={handleBreak}
                       disabled={submitting}
-                      className="admin-btn admin-btn-secondary"
-                      style={{ width: "100%" }}
+                      className="admin-btn admin-btn-secondary w-full"
                     >
                       Pauza (30 min)
                     </button>
@@ -663,15 +653,13 @@ export default function Attendance() {
                   <button
                     onClick={() => handlePunch("departure")}
                     disabled={submitting}
-                    className="admin-btn admin-btn-primary"
-                    style={{ width: "100%" }}
+                    className="admin-btn admin-btn-primary w-full"
                   >
                     {submitting ? "Zpracovávám..." : "Odchod"}
                   </button>
                   <button
                     onClick={() => setShowLeaveModal(true)}
-                    className="admin-btn admin-btn-secondary"
-                    style={{ width: "100%" }}
+                    className="admin-btn admin-btn-secondary w-full"
                   >
                     Žádost o nepřítomnost
                   </button>
@@ -703,16 +691,14 @@ export default function Attendance() {
                 <button
                   onClick={() => handlePunch("arrival")}
                   disabled={submitting}
-                  className="admin-btn admin-btn-primary"
-                  style={{ width: "100%" }}
+                  className="admin-btn admin-btn-primary w-full"
                 >
                   {submitting ? "Zpracovávám..." : "Příchod"}
                 </button>
 
                 <button
                   onClick={() => setShowLeaveModal(true)}
-                  className="admin-btn admin-btn-secondary"
-                  style={{ width: "100%" }}
+                  className="admin-btn admin-btn-secondary w-full"
                 >
                   Žádost o nepřítomnost
                 </button>
@@ -877,11 +863,10 @@ export default function Attendance() {
               </div>
               <div style={{ marginTop: "0.75rem" }}>
                 <div
-                  className="text-secondary"
+                  className="text-secondary text-sm"
                   style={{
                     display: "flex",
                     justifyContent: "space-between",
-                    fontSize: "0.8125rem",
                     marginBottom: "0.5rem",
                   }}
                 >
@@ -905,8 +890,8 @@ export default function Attendance() {
                 </div>
                 {data.monthly_fund.leave_hours > 0 && (
                   <div
-                    className="text-muted"
-                    style={{ fontSize: "0.75rem", marginTop: "0.375rem" }}
+                    className="text-muted text-xs"
+                    style={{ marginTop: "0.375rem" }}
                   >
                     {"Pokryto: "}
                     {data.monthly_fund.covered}h (práce{" "}
diff --git a/src/admin/pages/InvoiceDetail.tsx b/src/admin/pages/InvoiceDetail.tsx
index a43a617..cfd0cec 100644
--- a/src/admin/pages/InvoiceDetail.tsx
+++ b/src/admin/pages/InvoiceDetail.tsx
@@ -270,7 +270,7 @@ function SortableInvoiceRow({
           </select>
         </td>
       ) : null}
-      <td style={{ textAlign: "right", fontWeight: 600, whiteSpace: "nowrap" }}>
+      <td className="text-right fw-600 whitespace-nowrap">
         {formatCurrency(lineTotal, currency)}
       </td>
       <td>
@@ -354,12 +354,7 @@ function SortableInvoiceEditRow({
           </svg>
         </button>
       </td>
-      <td
-        className="text-tertiary"
-        style={{ textAlign: "center", fontWeight: 500 }}
-      >
-        {index + 1}
-      </td>
+      <td className="text-tertiary text-center fw-500">{index + 1}</td>
       <td>
         <input
           type="text"
@@ -1371,10 +1366,7 @@ export default function InvoiceDetail() {
                     ))}
                   </select>
                   {form.due_date && (
-                    <span
-                      className="text-tertiary"
-                      style={{ fontSize: "0.75rem", marginTop: "0.25rem" }}
-                    >
+                    <span className="text-tertiary text-xs mt-1">
                       Splatnost:{" "}
                       {new Date(form.due_date).toLocaleDateString("cs-CZ")}
                     </span>
@@ -1448,10 +1440,7 @@ export default function InvoiceDetail() {
                 </FormField>
                 <FormField label="DPH">
                   <div className="flex-row-gap">
-                    <label
-                      className="admin-form-checkbox"
-                      style={{ whiteSpace: "nowrap" }}
-                    >
+                    <label className="admin-form-checkbox whitespace-nowrap">
                       <input
                         type="checkbox"
                         checked={!!form.apply_vat}
@@ -1809,7 +1798,7 @@ export default function InvoiceDetail() {
           {invoice.paid_date && (
             <div className="admin-form-row mt-2">
               <FormField label="Datum úhrady">
-                <div style={{ color: "var(--success)", fontWeight: 500 }}>
+                <div className="fw-500" style={{ color: "var(--success)" }}>
                   {formatDate(invoice.paid_date)}
                 </div>
               </FormField>
@@ -1954,16 +1943,13 @@ export default function InvoiceDetail() {
                           : 0;
                         return (
                           <tr key={item.id || index}>
-                            <td
-                              className="text-tertiary"
-                              style={{ textAlign: "center", fontWeight: 500 }}
-                            >
+                            <td className="text-tertiary text-center fw-500">
                               {index + 1}
                             </td>
                             <td className="fw-500">
                               {item.description || "\u2014"}
                             </td>
-                            <td style={{ textAlign: "center" }}>
+                            <td className="text-center">
                               {item.quantity}{" "}
                               {item.unit && (
                                 <span className="text-tertiary">
@@ -1971,7 +1957,7 @@ export default function InvoiceDetail() {
                                 </span>
                               )}
                             </td>
-                            <td style={{ textAlign: "center" }}>
+                            <td className="text-center">
                               {item.unit || "\u2014"}
                             </td>
                             <td className="admin-mono text-right">
@@ -1980,16 +1966,13 @@ export default function InvoiceDetail() {
                                 invoice.currency,
                               )}
                             </td>
-                            <td style={{ textAlign: "center" }}>
+                            <td className="text-center">
                               {Number(invoice.apply_vat)
                                 ? Number(item.vat_rate)
                                 : 0}
                               %
                             </td>
-                            <td
-                              className="admin-mono"
-                              style={{ textAlign: "right", fontWeight: 600 }}
-                            >
+                            <td className="admin-mono text-right fw-600">
                               {formatCurrency(
                                 lineSubtotal + lineVat,
                                 invoice.currency,
diff --git a/src/admin/pages/Invoices.tsx b/src/admin/pages/Invoices.tsx
index c3467dd..9a12b8b 100644
--- a/src/admin/pages/Invoices.tsx
+++ b/src/admin/pages/Invoices.tsx
@@ -56,7 +56,7 @@ function formatCzkWithDetail(
   if (!Array.isArray(amounts) || amounts.length === 0)
     return { value: "0 Kč", detail: null };
   const hasForeign = amounts.some((a) => a.currency !== "CZK");
-  if (hasForeign && totalCzk !== null && totalCzk !== undefined) {
+  if (hasForeign && totalCzk != null) {
     return {
       value: formatCurrency(totalCzk, "CZK"),
       detail: formatMultiCurrency(amounts),
diff --git a/src/admin/pages/OfferDetail.tsx b/src/admin/pages/OfferDetail.tsx
index f34142f..0582faf 100644
--- a/src/admin/pages/OfferDetail.tsx
+++ b/src/admin/pages/OfferDetail.tsx
@@ -180,9 +180,7 @@ function SortableItemRow({
           </button>
         </td>
       )}
-      <td style={{ textAlign: "center", color: "var(--text-tertiary)" }}>
-        {index + 1}
-      </td>
+      <td className="text-center text-tertiary">{index + 1}</td>
       <td style={{ verticalAlign: "top" }}>
         <div
           style={{ display: "flex", flexDirection: "column", gap: "0.25rem" }}
@@ -191,10 +189,9 @@ function SortableItemRow({
             type="text"
             value={item.description}
             onChange={(e) => onUpdate("description", e.target.value)}
-            className="admin-form-input"
+            className="admin-form-input fw-500"
             placeholder="Název položky"
             readOnly={readOnly}
-            style={{ fontWeight: 500 }}
           />
           <input
             type="text"
@@ -240,7 +237,7 @@ function SortableItemRow({
           readOnly={readOnly}
         />
       </td>
-      <td style={{ textAlign: "center" }}>
+      <td className="text-center">
         <input
           type="checkbox"
           checked={item.is_included_in_total}
@@ -248,10 +245,7 @@ function SortableItemRow({
           disabled={readOnly}
         />
       </td>
-      <td
-        className="admin-mono"
-        style={{ textAlign: "right", fontWeight: 600 }}
-      >
+      <td className="admin-mono text-right fw-600">
         {formatCurrency(lineTotal, currency)}
       </td>
       {!readOnly && (
@@ -874,11 +868,10 @@ export default function OfferDetail() {
               {isEdit ? `Nabídka ${form.quotation_number}` : "Nová nabídka"}
               {isInvalidated && (
                 <span
-                  className="admin-badge admin-badge-danger"
+                  className="admin-badge admin-badge-danger text-xs"
                   style={{
                     marginLeft: "0.75rem",
                     verticalAlign: "middle",
-                    fontSize: "0.75rem",
                   }}
                 >
                   Zneplatněna
@@ -1208,10 +1201,7 @@ export default function OfferDetail() {
                     </option>
                   ))}
                 </select>
-                <label
-                  className="admin-form-checkbox"
-                  style={{ whiteSpace: "nowrap" }}
-                >
+                <label className="admin-form-checkbox whitespace-nowrap">
                   <input
                     type="checkbox"
                     checked={form.apply_vat}
@@ -1672,7 +1662,7 @@ export default function OfferDetail() {
                   <FormField label="Příloha (PDF)">
                     {orderAttachment ? (
                       <div className="flex-row gap-2">
-                        <span style={{ fontSize: "0.875rem" }}>
+                        <span className="text-md">
                           {orderAttachment.name}{" "}
                           <span className="text-tertiary">
                             ({(orderAttachment.size / 1024).toFixed(0)} KB)
diff --git a/src/admin/pages/Offers.tsx b/src/admin/pages/Offers.tsx
index 3624320..4186390 100644
--- a/src/admin/pages/Offers.tsx
+++ b/src/admin/pages/Offers.tsx
@@ -814,8 +814,8 @@ export default function Offers() {
                     <tr>
                       <td
                         colSpan={8}
-                        className="text-muted"
-                        style={{ textAlign: "center", padding: "1.5rem" }}
+                        className="text-muted text-center"
+                        style={{ padding: "1.5rem" }}
                       >
                         Žádné nabídky odpovídající hledání.
                       </td>
@@ -879,8 +879,8 @@ export default function Offers() {
               <div className="admin-modal-header">
                 <h2 className="admin-modal-title">Vytvořit objednávku</h2>
                 <p
-                  className="text-secondary"
-                  style={{ marginTop: "0.25rem", fontSize: "0.875rem" }}
+                  className="text-secondary text-md"
+                  style={{ marginTop: "0.25rem" }}
                 >
                   Nabídka:{" "}
                   <strong>{orderModal.quotation?.quotation_number}</strong>
@@ -917,7 +917,7 @@ export default function Offers() {
                           <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z" />
                           <polyline points="14 2 14 8 20 8" />
                         </svg>
-                        <span style={{ fontSize: "0.875rem" }}>
+                        <span className="text-md">
                           {orderAttachment.name}{" "}
                           <span className="text-tertiary">
                             ({(orderAttachment.size / 1024).toFixed(0)} KB)
@@ -944,11 +944,9 @@ export default function Offers() {
                       </div>
                     ) : (
                       <label
-                        className="admin-btn admin-btn-secondary admin-btn-sm"
+                        className="admin-btn admin-btn-secondary admin-btn-sm inline-flex"
                         style={{
                           cursor: "pointer",
-                          display: "inline-flex",
-                          alignItems: "center",
                           gap: "0.4rem",
                         }}
                       >
diff --git a/src/admin/pages/ReceivedInvoices.tsx b/src/admin/pages/ReceivedInvoices.tsx
index 3246cb0..dbc67bf 100644
--- a/src/admin/pages/ReceivedInvoices.tsx
+++ b/src/admin/pages/ReceivedInvoices.tsx
@@ -115,7 +115,7 @@ function formatCzkWithDetail(
     return { value: "0 Kč", detail: null };
   }
   const hasForeign = amounts.some((a) => a.currency !== "CZK");
-  if (hasForeign && totalCzk !== null && totalCzk !== undefined) {
+  if (hasForeign && totalCzk != null) {
     return {
       value: formatCurrency(totalCzk, "CZK"),
       detail: formatMultiCurrency(amounts),
@@ -709,9 +709,9 @@ export default function ReceivedInvoices({
               <p>Žádné přijaté faktury v tomto měsíci.</p>
               {hasPermission("invoices.create") && (
                 <p
+                  className="text-md"
                   style={{
                     color: "var(--text-tertiary)",
-                    fontSize: "0.875rem",
                   }}
                 >
                   Nahrajte faktury tlačítkem výše.
@@ -780,7 +780,8 @@ export default function ReceivedInvoices({
                       />
                     </th>
                     <th
-                      style={{ textAlign: "right", cursor: "pointer" }}
+                      className="text-right"
+                      style={{ cursor: "pointer" }}
                       onClick={() => handleSort("amount")}
                     >
                       Částka{" "}
@@ -959,9 +960,9 @@ export default function ReceivedInvoices({
                     Vybrat soubory
                   </button>
                   <span
+                    className="text-sm"
                     style={{
                       marginLeft: "0.75rem",
-                      fontSize: "0.8125rem",
                       color: "var(--text-tertiary)",
                     }}
                   >
@@ -1106,8 +1107,8 @@ export default function ReceivedInvoices({
                         </div>
                         {uploadMeta[idx]?.amount && (
                           <div
+                            className="text-xs"
                             style={{
-                              fontSize: "0.75rem",
                               color: "var(--text-tertiary)",
                               marginTop: "-0.25rem",
                               marginBottom: "0.5rem",
@@ -1320,8 +1321,8 @@ export default function ReceivedInvoices({
                         </div>
                         {editInvoice.amount && (
                           <div
+                            className="text-xs"
                             style={{
-                              fontSize: "0.75rem",
                               color: "var(--text-tertiary)",
                               marginBottom: "0.75rem",
                             }}
diff --git a/src/admin/pages/Settings.tsx b/src/admin/pages/Settings.tsx
index e673073..a7e5b4e 100644
--- a/src/admin/pages/Settings.tsx
+++ b/src/admin/pages/Settings.tsx
@@ -639,17 +639,16 @@ export default function Settings() {
                 </div>
                 <div>
                   <div
+                    className="fw-500 text-md"
                     style={{
-                      fontWeight: 500,
                       color: "var(--text-primary)",
-                      fontSize: "0.875rem",
                     }}
                   >
                     Povinné dvoufaktorové ověření (2FA)
                   </div>
                   <div
+                    className="text-xs"
                     style={{
-                      fontSize: "0.75rem",
                       color: "var(--text-secondary)",
                     }}
                   >
@@ -781,16 +780,16 @@ export default function Settings() {
                     <tr key={role.id}>
                       <td>
                         <div
+                          className="fw-500"
                           style={{
-                            fontWeight: 500,
                             color: "var(--text-primary)",
                           }}
                         >
                           {role.display_name}
                         </div>
                         <div
+                          className="text-xs"
                           style={{
-                            fontSize: "0.75rem",
                             color: "var(--text-tertiary)",
                           }}
                         >
@@ -1077,9 +1076,9 @@ export default function Settings() {
                       />
                     </FormField>
                     <small
+                      className="text-xs"
                       style={{
                         color: "var(--text-tertiary)",
-                        fontSize: "0.75rem",
                       }}
                     >
                       Změna se projeví po restartu serveru
@@ -1179,10 +1178,9 @@ export default function Settings() {
                             />
                           )}
                           <div
+                            className="fw-600 text-md"
                             style={{
-                              fontWeight: 600,
                               marginBottom: "0.5rem",
-                              fontSize: "0.875rem",
                             }}
                           >
                             {cfg.label}
@@ -1355,8 +1353,8 @@ export default function Settings() {
                 <div className="admin-card-body">
                   {systemInfo ? (
                     <table
+                      className="w-full"
                       style={{
-                        width: "100%",
                         fontSize: "0.85rem",
                         borderCollapse: "collapse",
                       }}
@@ -1374,16 +1372,16 @@ export default function Settings() {
                         ).map(([label, val]) => (
                           <tr key={label}>
                             <td
+                              className="whitespace-nowrap"
                               style={{
                                 padding: "6px 12px 6px 0",
                                 color: "var(--text-secondary)",
-                                whiteSpace: "nowrap",
                                 width: 160,
                               }}
                             >
                               {label}
                             </td>
-                            <td style={{ padding: "6px 0", fontWeight: 500 }}>
+                            <td className="fw-500" style={{ padding: "6px 0" }}>
                               {val}
                             </td>
                           </tr>
@@ -1516,9 +1514,9 @@ export default function Settings() {
                               </span>
                               {info?.configured && (
                                 <span
+                                  className="text-xs"
                                   style={{
                                     marginLeft: 8,
-                                    fontSize: "0.75rem",
                                     color: "var(--text-tertiary)",
                                   }}
                                 >
@@ -1548,8 +1546,7 @@ export default function Settings() {
                 <button
                   onClick={handleSaveSystemSettings}
                   disabled={sysSettingsSaving}
-                  className="admin-btn admin-btn-primary"
-                  style={{ width: "100%" }}
+                  className="admin-btn admin-btn-primary w-full"
                 >
                   {sysSettingsSaving ? (
                     <>
@@ -1637,9 +1634,9 @@ export default function Settings() {
                     />
                     {!editingRole && (
                       <small
+                        className="text-xs"
                         style={{
                           color: "var(--text-tertiary)",
-                          fontSize: "0.75rem",
                         }}
                       >
                         Pouze malá písmena, čísla a pomlčky. Nelze později
diff --git a/src/routes/admin/dashboard.ts b/src/routes/admin/dashboard.ts
index 5ec5c2b..fb5555e 100644
--- a/src/routes/admin/dashboard.ts
+++ b/src/routes/admin/dashboard.ts
@@ -3,6 +3,7 @@ import prisma from "../../config/database";
 import { requireAuth } from "../../middleware/auth";
 import { success } from "../../utils/response";
 import { localTimeStr } from "../../utils/date";
+import { toCzk } from "../../services/exchange-rates";
 
 export default async function dashboardRoutes(
   fastify: FastifyInstance,
@@ -206,10 +207,13 @@ export default async function dashboardRoutes(
           }),
         ),
         unpaid_count: unpaidCount,
-        revenue_czk:
-          revenueByCurrency["CZK"] != null
-            ? Math.round(revenueByCurrency["CZK"] * 100) / 100
-            : null,
+        revenue_czk: await (async () => {
+          let total = 0;
+          for (const [cur, amount] of Object.entries(revenueByCurrency)) {
+            total += await toCzk(Math.round(amount * 100) / 100, cur);
+          }
+          return Math.round(total * 100) / 100;
+        })(),
       };
       result.unpaid_invoices = unpaidCount;
     }
diff --git a/src/routes/admin/invoices-pdf.ts b/src/routes/admin/invoices-pdf.ts
index ee2fe52..254437b 100644
--- a/src/routes/admin/invoices-pdf.ts
+++ b/src/routes/admin/invoices-pdf.ts
@@ -5,6 +5,8 @@ import { requirePermission } from "../../middleware/auth";
 import { localDateCzStr } from "../../utils/date";
 import { nasFinancialsManager } from "../../services/nas-financials-manager";
 import { htmlToPdf } from "../../utils/html-to-pdf";
+import { getRate } from "../../services/exchange-rates";
+import { localDateStr } from "../../utils/date";
 
 /* ── Helpers ─────────────────────────────────────────────────────── */
 
@@ -358,9 +360,12 @@ export default async function invoicesPdfRoutes(
         // QR generation failed — leave empty
       }
 
-      // VAT recapitulation (always in CZK)
+      // VAT recapitulation (always in CZK — Czech tax requirement)
       const isForeign = currency.toUpperCase() !== "CZK";
-      const cnbRate = 1.0; // Skip CNB rate conversion
+      const issueDateStr = invoice.issue_date
+        ? localDateStr(new Date(invoice.issue_date))
+        : undefined;
+      const cnbRate = isForeign ? await getRate(currency, issueDateStr) : 1.0;
       const vatRates = [21, 12, 0];
       const vatRecap: Array<{
         rate: number;
@@ -1007,6 +1012,17 @@ ${indentCSS}
       <tbody>
         ${vatRecapHtml}
       </tbody>
+      ${
+        isForeign
+          ? `<tfoot>
+        <tr>
+          <td colspan="4" style="font-size:0.7em; color:#666; padding-top:6px; text-align:left;">
+            Přepočet kurzem ČNB ke dni ${formatDate(invoice.issue_date)}: 1 ${escapeHtml(currency)} = ${cnbRate.toFixed(3).replace(".", ",")} CZK
+          </td>
+        </tr>
+      </tfoot>`
+          : ""
+      }
     </table>
   </div>
 
diff --git a/src/routes/admin/received-invoices.ts b/src/routes/admin/received-invoices.ts
index 310e591..fcd903c 100644
--- a/src/routes/admin/received-invoices.ts
+++ b/src/routes/admin/received-invoices.ts
@@ -12,6 +12,7 @@ import {
   UpdateReceivedInvoiceSchema,
 } from "../../schemas/received-invoices.schema";
 import { nasFinancialsManager } from "../../services/nas-financials-manager";
+import { toCzk } from "../../services/exchange-rates";
 
 const VALID_STATUSES = ["unpaid", "paid"] as const;
 const ALLOWED_SORT_FIELDS = [
@@ -108,12 +109,15 @@ export default async function receivedInvoicesRoutes(
           }));
       };
 
-      const sumCzk = (
+      const sumCzk = async (
         invs: typeof monthInvoices,
         field: "amount" | "vat_amount",
       ) => {
         let total = 0;
-        for (const inv of invs) total += Number(inv[field]) || 0;
+        for (const inv of invs) {
+          const amount = Number(inv[field]) || 0;
+          total += await toCzk(amount, inv.currency);
+        }
         return Math.round(total * 100) / 100;
       };
 
@@ -124,11 +128,11 @@ export default async function receivedInvoicesRoutes(
 
       return success(reply, {
         total_month: aggregateByCurrency(monthInvoices, "amount"),
-        total_month_czk: sumCzk(monthInvoices, "amount"),
+        total_month_czk: await sumCzk(monthInvoices, "amount"),
         vat_month: aggregateByCurrency(monthInvoices, "vat_amount"),
-        vat_month_czk: sumCzk(monthInvoices, "vat_amount"),
+        vat_month_czk: await sumCzk(monthInvoices, "vat_amount"),
         unpaid: aggregateByCurrency(allUnpaid, "amount"),
-        unpaid_czk: sumCzk(allUnpaid, "amount"),
+        unpaid_czk: await sumCzk(allUnpaid, "amount"),
         unpaid_count: allUnpaid.length,
         month_count: monthInvoices.length,
       });
diff --git a/src/services/exchange-rates.ts b/src/services/exchange-rates.ts
new file mode 100644
index 0000000..6a5e7a7
--- /dev/null
+++ b/src/services/exchange-rates.ts
@@ -0,0 +1,65 @@
+/**
+ * Czech National Bank (ČNB) exchange rate service.
+ * Fetches daily rates and caches them.
+ * API: https://api.cnb.cz/cnbapi/exrates/daily
+ */
+
+interface CnbRate {
+  currencyCode: string;
+  rate: number;
+  amount: number;
+}
+
+const rateCache: Record<string, Record<string, number>> = {};
+
+async function fetchRatesForDate(
+  date?: string,
+): Promise<Record<string, number>> {
+  const key = date || "today";
+  if (rateCache[key]) return rateCache[key];
+
+  try {
+    let url = "https://api.cnb.cz/cnbapi/exrates/daily?lang=EN";
+    if (date) url += `&date=${date}`;
+
+    const response = await fetch(url);
+    if (!response.ok) throw new Error(`CNB API: ${response.status}`);
+
+    const data = (await response.json()) as { rates: CnbRate[] };
+    const rates: Record<string, number> = { CZK: 1 };
+
+    for (const r of data.rates) {
+      rates[r.currencyCode] = r.rate / r.amount;
+    }
+
+    rateCache[key] = rates;
+    return rates;
+  } catch (err) {
+    console.error("Failed to fetch CNB exchange rates:", err);
+    if (rateCache["today"]) return rateCache["today"];
+    return { CZK: 1, EUR: 25, USD: 22, GBP: 28 };
+  }
+}
+
+/** Convert an amount from a given currency to CZK using CNB rates */
+export async function toCzk(
+  amount: number,
+  currency: string,
+  date?: string,
+): Promise<number> {
+  if (currency === "CZK") return amount;
+  const rates = await fetchRatesForDate(date);
+  const rate = rates[currency];
+  if (!rate) return amount;
+  return Math.round(amount * rate * 100) / 100;
+}
+
+/** Get CNB rate for a currency (CZK per 1 unit), optionally for a specific date */
+export async function getRate(
+  currency: string,
+  date?: string,
+): Promise<number> {
+  if (currency === "CZK") return 1;
+  const rates = await fetchRatesForDate(date);
+  return rates[currency] || 1;
+}
diff --git a/src/services/invoices.service.ts b/src/services/invoices.service.ts
index 9a255ff..0132e5d 100644
--- a/src/services/invoices.service.ts
+++ b/src/services/invoices.service.ts
@@ -1,4 +1,5 @@
 import prisma from "../config/database";
+import { toCzk } from "./exchange-rates";
 
 // Status transition rules matching PHP
 const VALID_TRANSITIONS: Record<string, string[]> = {
@@ -186,10 +187,11 @@ export async function getInvoiceStats(queryMonth?: number, queryYear?: number) {
       }));
   };
 
-  const sumCzk = (invoices: typeof allInvoices) => {
+  const sumCzk = async (invoices: typeof allInvoices) => {
     let total = 0;
     for (const inv of invoices) {
-      total += invoiceTotalWithVat(inv); // Simplified: no real FX conversion
+      const amount = invoiceTotalWithVat(inv);
+      total += await toCzk(amount, inv.currency || "CZK");
     }
     return Math.round(total * 100) / 100;
   };
@@ -224,18 +226,24 @@ export async function getInvoiceStats(queryMonth?: number, queryYear?: number) {
   let vatCzk = 0;
   for (const [, v] of Object.entries(vatMap)) vatCzk += v;
 
+  // VAT also needs conversion
+  let vatCzkConverted = 0;
+  for (const [cur, amount] of Object.entries(vatMap)) {
+    vatCzkConverted += await toCzk(amount, cur);
+  }
+
   return {
     paid_month: aggregateByCurrency(paidInvoices),
-    paid_month_czk: sumCzk(paidInvoices),
+    paid_month_czk: await sumCzk(paidInvoices),
     paid_month_count: paidInvoices.length,
     awaiting: aggregateByCurrency(awaitingInvoices),
-    awaiting_czk: sumCzk(awaitingInvoices),
+    awaiting_czk: await sumCzk(awaitingInvoices),
     awaiting_count: awaitingInvoices.length,
     overdue: aggregateByCurrency(overdueInvoices),
-    overdue_czk: sumCzk(overdueInvoices),
+    overdue_czk: await sumCzk(overdueInvoices),
     overdue_count: overdueInvoices.length,
     vat_month: vatAmounts,
-    vat_month_czk: Math.round(vatCzk * 100) / 100,
+    vat_month_czk: Math.round(vatCzkConverted * 100) / 100,
     month,
     year,
   };