diff --git a/src/lib/repo-analytics-utils.ts b/src/lib/repo-analytics-utils.ts
index 9c9c87d44..51c22924e 100644
--- a/src/lib/repo-analytics-utils.ts
+++ b/src/lib/repo-analytics-utils.ts
@@ -9,15 +9,21 @@ export interface ParsedRepo {
 
 /**
  * Validates and parses a raw "owner/repo" string.
+ * Strips a single leading slash and collapses consecutive slashes before
+ * validating, so inputs like "/owner/repo" or "owner//repo" (e.g. from
+ * referrer headers or query params) normalise to "owner/repo" instead of
+ * silently failing to match.
  * Returns the split components on success, or null if the value is invalid.
  */
 export function parseRepoParam(raw: string): ParsedRepo | null {
   const trimmed = raw.trim();
-  const match = REPO_IDENTIFIER_RE.exec(trimmed);
+  const withoutLeadingSlash = trimmed.startsWith("/")
+    ? trimmed.slice(1)
+    : trimmed;
+  const normalised = withoutLeadingSlash.replace(/\/{2,}/g, "/");
+  const match = REPO_IDENTIFIER_RE.exec(normalised);
   if (!match) return null;
-
   const [, owner, repo] = match;
   if (repo === "." || repo === "..") return null;
-
   return { owner, repo };
 }
diff --git a/test/repo-analytics-utils-sanitize.test.ts b/test/repo-analytics-utils-sanitize.test.ts
new file mode 100644
index 000000000..4f2d8e852
--- /dev/null
+++ b/test/repo-analytics-utils-sanitize.test.ts
@@ -0,0 +1,32 @@
+import { describe, it, expect } from "vitest";
+import { parseRepoParam } from "@/lib/repo-analytics-utils";
+
+describe("parseRepoParam — input sanitisation", () => {
+  it("strips a single leading slash before validating", () => {
+    expect(parseRepoParam("/owner/repo")).toEqual({
+      owner: "owner",
+      repo: "repo",
+    });
+  });
+
+  it("collapses consecutive slashes before validating", () => {
+    expect(parseRepoParam("owner//repo")).toEqual({
+      owner: "owner",
+      repo: "repo",
+    });
+  });
+
+  it("handles mixed leading slash, double slashes, and surrounding spaces", () => {
+    expect(parseRepoParam("  /owner//repo  ")).toEqual({
+      owner: "owner",
+      repo: "repo",
+    });
+  });
+
+  it("leaves normal input unchanged", () => {
+    expect(parseRepoParam("facebook/react")).toEqual({
+      owner: "facebook",
+      repo: "react",
+    });
+  });
+});