diff --git a/src/components/admin/__tests__/pulse-day-mean-card.test.tsx b/src/components/admin/__tests__/pulse-day-mean-card.test.tsx
new file mode 100644
index 000000000..926de7ea6
--- /dev/null
+++ b/src/components/admin/__tests__/pulse-day-mean-card.test.tsx
@@ -0,0 +1,116 @@
+/**
+ * The pulse day-mean admin card.
+ *
+ *   1. apply is offered only after a dry run finished in the last seven days,
+ *      and never while a dry run is queued or running;
+ *   2. a finished dry run shows its figures and the per-account ordinals;
+ *   3. the active method reads in the header, in German too.
+ *
+ * Mutation check: drop `hasFreshDryRun` from `canApply` and case 1 goes red.
+ */
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { renderToStaticMarkup } from "react-dom/server";
+import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
+
+import { PulseDayMeanCard } from "@/components/admin/pulse-day-mean-card";
+import { I18nProvider } from "@/lib/i18n/context";
+import { queryKeys } from "@/lib/query-keys";
+import type { PulseDayMeanStatus } from "@/lib/validations/pulse-day-mean";
+
+const RESULT = {
+  accounts: 2,
+  daysCompared: 412,
+  daysChangedOver1Bpm: 37,
+  maxChangeBpm: 6.4,
+  distribution: [
+    { bucket: "0-1" as const, days: 375 },
+    { bucket: "1-2" as const, days: 30 },
+    { bucket: "2-5" as const, days: 6 },
+    { bucket: "5+" as const, days: 1 },
+  ],
+  perAccount: [
+    { account: "#1", days: 400, changedOver1Bpm: 36 },
+    { account: "#2", days: 12, changedOver1Bpm: 1 },
+  ],
+};
+
+const status = (
+  lastDryRun: PulseDayMeanStatus["lastDryRun"],
+  method: PulseDayMeanStatus["method"] = "hour_mean_v1",
+): PulseDayMeanStatus => ({ method, appliedAt: null, lastDryRun });
+
+const done = (finishedAt: string) => ({
+  status: "done" as const,
+  startedAt: finishedAt,
+  finishedAt,
+  result: RESULT,
+});
+
+function render(s: PulseDayMeanStatus, locale: "en" | "de" = "en"): string {
+  const client = new QueryClient();
+  client.setQueryData(queryKeys.adminPulseDayMean(), s);
+  return renderToStaticMarkup(
+    <QueryClientProvider client={client}>
+      <I18nProvider initialLocale={locale}>
+        <PulseDayMeanCard />
+      </I18nProvider>
+    </QueryClientProvider>,
+  );
+}
+
+/** Whether the apply button renders disabled. */
+function applyDisabled(html: string): boolean {
+  const at = html.indexOf('data-testid="admin-pulse-day-mean-apply"');
+  const tag = html.slice(
+    html.lastIndexOf("<button", at),
+    html.indexOf(">", at),
+  );
+  return /\sdisabled=""/.test(tag);
+}
+
+beforeEach(() => {
+  vi.useFakeTimers({ toFake: ["Date"] });
+  vi.setSystemTime(new Date("2026-10-16T12:00:00Z"));
+});
+afterEach(() => vi.useRealTimers());
+
+describe("PulseDayMeanCard", () => {
+  it("offers apply only after a fresh, finished dry run", () => {
+    expect(applyDisabled(render(status(null)))).toBe(true);
+    expect(
+      applyDisabled(render(status(done("2026-10-08T12:00:00.000Z")))),
+    ).toBe(true);
+    expect(
+      applyDisabled(
+        render(
+          status({
+            status: "running",
+            startedAt: "2026-10-16T11:00:00.000Z",
+            finishedAt: null,
+            result: null,
+          }),
+        ),
+      ),
+    ).toBe(true);
+    expect(
+      applyDisabled(render(status(done("2026-10-15T12:00:00.000Z")))),
+    ).toBe(false);
+  });
+
+  it("shows what the dry run found", () => {
+    const html = render(status(done("2026-10-15T12:00:00.000Z")));
+    expect(html).toContain("412");
+    expect(html).toContain("37");
+    expect(html).toContain("6.4 bpm");
+    expect(html).toContain("5+ bpm");
+    expect(html).toContain("Account #2");
+    expect(html).toContain("36 of 400 days move");
+  });
+
+  it("names the active method, in German too", () => {
+    expect(render(status(null))).toContain("Every hour equal");
+    const de = render(status(null, "weighted_hour_mean_v2"), "de");
+    expect(de).toContain("Dünne Stunden gewichtet");
+    expect(de).toContain("Probelauf");
+  });
+});