diff --git a/src/components/TopRepos.tsx b/src/components/TopRepos.tsx
index baacc0268..9434c09bb 100644
--- a/src/components/TopRepos.tsx
+++ b/src/components/TopRepos.tsx
@@ -7,6 +7,7 @@ import type { RepoHealthScore } from "@/types/repo-health";
 import RepoHealthPanel from "@/components/RepoHealthPanel";
 import RepoActivityDrawer from "@/components/RepoActivityDrawer";
 import { Search, Bookmark } from "lucide-react";
+import { getCodebaseSizeFromLanguages, type CodebaseSize } from "@/lib/codebase-size";
 
 interface RepoItemProps {
   repo: Repo;
@@ -53,6 +54,22 @@ const RepoItem = memo(({
         : "bg-[var(--destructive)]/15 text-[var(--destructive)] border border-[var(--destructive)]/25";
 
   const visibleLanguages = repo.languages ? getVisibleLanguages(repo.languages) : [];
+  const codebaseSize = getCodebaseSizeFromLanguages(repo.languages);
+
+  const sizeConfig: Record<CodebaseSize, { classes: string; ariaLabel: string }> = {
+    Small: {
+      classes: "bg-emerald-500/10 text-emerald-400 border-emerald-500/20",
+      ariaLabel: "Small codebase, under 50KB total code",
+    },
+    Medium: {
+      classes: "bg-amber-500/10 text-amber-400 border-amber-500/20",
+      ariaLabel: "Medium codebase, between 50KB and 500KB total code",
+    },
+    Large: {
+      classes: "bg-blue-500/10 text-blue-400 border-blue-500/20",
+      ariaLabel: "Large codebase, over 500KB total code",
+    },
+  };
 
   return (
     <li>
@@ -154,7 +171,7 @@ const RepoItem = memo(({
         />
       </div>
       <div className="mt-2 min-h-6">
-        {visibleLanguages.length > 0 && (
+        {(visibleLanguages.length > 0 || codebaseSize) && (
           <div className="flex flex-wrap gap-1.5 text-[11px] text-[var(--muted-foreground)]">
             {visibleLanguages.map((language) => (
               <span
@@ -170,6 +187,15 @@ const RepoItem = memo(({
                 <span>{language.percentage}%</span>
               </span>
             ))}
+            {codebaseSize && (
+              <span
+                className={`inline-flex items-center gap-1 rounded-full border px-2 py-0.5 font-medium ${sizeConfig[codebaseSize].classes}`}
+                aria-label={sizeConfig[codebaseSize].ariaLabel}
+                title={sizeConfig[codebaseSize].ariaLabel}
+              >
+                {codebaseSize} Codebase
+              </span>
+            )}
           </div>
         )}
       </div>
diff --git a/src/lib/codebase-size.ts b/src/lib/codebase-size.ts
new file mode 100644
index 000000000..ba2398258
--- /dev/null
+++ b/src/lib/codebase-size.ts
@@ -0,0 +1,42 @@
+/**
+ * Pure utility that classifies a repository's codebase size based on total
+ * language bytes returned by the GitHub REST API (`/repos/:owner/:repo/languages`).
+ *
+ * Thresholds (per issue #2601):
+ *   < 50 KB  (51,200 bytes)  → "Small"
+ *   50–500 KB (512,000 bytes) → "Medium"
+ *   > 500 KB                  → "Large"
+ */
+
+export type CodebaseSize = "Small" | "Medium" | "Large";
+
+const SMALL_THRESHOLD = 51_200; // 50 KB
+const LARGE_THRESHOLD = 512_000; // 500 KB
+
+/**
+ * Classifies a codebase by its total byte count.
+ */
+export function getCodebaseSize(totalBytes: number): CodebaseSize {
+  if (totalBytes < SMALL_THRESHOLD) return "Small";
+  if (totalBytes <= LARGE_THRESHOLD) return "Medium";
+  return "Large";
+}
+
+interface LanguageEntry {
+  bytes: number;
+}
+
+/**
+ * Convenience wrapper: sums `bytes` from a languages array and returns the
+ * codebase size classification.  Returns `null` when there is no language data.
+ */
+export function getCodebaseSizeFromLanguages(
+  languages: LanguageEntry[] | undefined
+): CodebaseSize | null {
+  if (!languages || languages.length === 0) return null;
+
+  const totalBytes = languages.reduce((sum, lang) => sum + lang.bytes, 0);
+  if (totalBytes <= 0) return null;
+
+  return getCodebaseSize(totalBytes);
+}