diff --git a/.gitignore b/.gitignore
index 83d4758..983249c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,6 +35,9 @@ yarn-error.log*
 /data/*.db-wal
 /data/*.db-shm
 
+# uploads (user content)
+/public/uploads/
+
 # env files (can opt-in for committing if needed)
 .env*
 
diff --git a/Dockerfile b/Dockerfile
index 96ca0d5..840b398 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -13,7 +13,8 @@ WORKDIR /app
 ENV NODE_ENV=production
 ENV NEXT_TELEMETRY_DISABLED=1
 
-RUN addgroup --system --gid 1001 nodejs && \
+RUN apk add --no-cache ffmpeg && \
+    addgroup --system --gid 1001 nodejs && \
     adduser --system --uid 1001 nextjs
 
 COPY --from=builder /app/public ./public
diff --git a/app/api/sounds/route.ts b/app/api/sounds/route.ts
index 1018ab9..f6cb921 100644
--- a/app/api/sounds/route.ts
+++ b/app/api/sounds/route.ts
@@ -6,6 +6,7 @@ import { writeFile, mkdir, unlink } from "fs/promises";
 import path from "path";
 import { v4 as uuidv4 } from "uuid";
 import { eq } from "drizzle-orm";
+import { convertOggToMp3 } from "@/lib/convert";
 
 const UPLOAD_DIR = path.join(process.cwd(), "public", "uploads", "sounds");
 
@@ -45,26 +46,34 @@ export async function POST(req: NextRequest) {
       if (!file.name.toLowerCase().endsWith(".ogg")) continue;
       if (file.size > 2 * 1024 * 1024) continue;
 
-      const ext = path.extname(file.name);
-      const filename = `${uuidv4()}${ext}`;
-      const filepath = path.join(UPLOAD_DIR, filename);
-      const bytes = await file.arrayBuffer();
-      await writeFile(filepath, Buffer.from(bytes));
+      const baseName = uuidv4();
+      const oggPath = path.join(UPLOAD_DIR, `${baseName}.ogg`);
+      const mp3Path = path.join(UPLOAD_DIR, `${baseName}.mp3`);
+
+      const bytes = await file.arrayBuffer();
+      await writeFile(oggPath, Buffer.from(bytes));
 
-      // compute duration from file size (approximate for OGG Vorbis ~64kbps)
       const duration = Math.round((file.size / (64 * 128)) * 10) / 10;
 
+      let storedFilename: string;
+      if (convertOggToMp3(oggPath, mp3Path)) {
+        await unlink(oggPath).catch(() => {});
+        storedFilename = `${baseName}.mp3`;
+      } else {
+        storedFilename = `${baseName}.ogg`;
+      }
+
       const id = uuidv4();
       db.insert(sounds).values({
         id,
-        originalName: file.name,
-        storedFilename: filename,
+        originalName: file.name.replace(/\.ogg$/i, ".mp3"),
+        storedFilename,
         duration: Math.min(duration, 6),
         uploadedBy: session.id,
         createdAt: new Date().toISOString(),
       }).run();
 
-      results.push({ url: `/uploads/sounds/${filename}`, originalName: file.name, duration: Math.min(duration, 6) });
+      results.push({ url: `/uploads/sounds/${storedFilename}`, originalName: file.name.replace(/\.ogg$/i, ".mp3"), duration: Math.min(duration, 6) });
     }
 
     return NextResponse.json({ sounds: results });
diff --git a/app/api/upload/sound/route.ts b/app/api/upload/sound/route.ts
index 0e602ab..f512a8d 100644
--- a/app/api/upload/sound/route.ts
+++ b/app/api/upload/sound/route.ts
@@ -2,9 +2,11 @@ import { NextRequest, NextResponse } from "next/server";
 import { getServerSession } from "@/lib/auth";
 import { db } from "@/lib/db";
 import { sounds } from "@/lib/db/schema";
-import { writeFile, mkdir } from "fs/promises";
+import { writeFile, mkdir, unlink } from "fs/promises";
 import path from "path";
 import { v4 as uuidv4 } from "uuid";
+import { convertOggToMp3 } from "@/lib/convert";
+import fs from "fs";
 
 const UPLOAD_DIR = path.join(process.cwd(), "public", "uploads", "sounds");
 
@@ -28,26 +30,38 @@ export async function POST(req: NextRequest) {
     }
 
     await mkdir(UPLOAD_DIR, { recursive: true });
-    const ext = path.extname(file.name);
-    const filename = `${uuidv4()}${ext}`;
-    const filepath = path.join(UPLOAD_DIR, filename);
-    const bytes = await file.arrayBuffer();
-    await writeFile(filepath, Buffer.from(bytes));
 
-    // approximate duration
+    const baseName = uuidv4();
+    const oggPath = path.join(UPLOAD_DIR, `${baseName}.ogg`);
+    const mp3Path = path.join(UPLOAD_DIR, `${baseName}.mp3`);
+
+    // save temporary OGG
+    const bytes = await file.arrayBuffer();
+    await writeFile(oggPath, Buffer.from(bytes));
+
+    // duration estimate
     const duration = Math.round((file.size / (64 * 128)) * 10) / 10;
 
+    // convert to MP3
+    let storedFilename: string;
+    if (convertOggToMp3(oggPath, mp3Path)) {
+      await unlink(oggPath).catch(() => {});
+      storedFilename = `${baseName}.mp3`;
+    } else {
+      storedFilename = `${baseName}.ogg`;
+    }
+
     const id = uuidv4();
     db.insert(sounds).values({
       id,
-      originalName: file.name,
-      storedFilename: filename,
+      originalName: file.name.replace(/\.ogg$/i, ".mp3"),
+      storedFilename,
       duration: Math.min(duration, 6),
       uploadedBy: session.id,
       createdAt: new Date().toISOString(),
     }).run();
 
-    return NextResponse.json({ url: `/uploads/sounds/${filename}` });
+    return NextResponse.json({ url: `/uploads/sounds/${storedFilename}` });
   } catch {
     return NextResponse.json({ error: "Upload failed" }, { status: 500 });
   }
diff --git a/lib/convert.ts b/lib/convert.ts
new file mode 100644
index 0000000..48a0e2c
--- /dev/null
+++ b/lib/convert.ts
@@ -0,0 +1,23 @@
+import { execSync } from "child_process";
+import fs from "fs";
+
+export function convertOggToMp3(inputPath: string, outputPath: string): boolean {
+  try {
+    execSync(
+      `ffmpeg -i "${inputPath}" -codec:a libmp3lame -b:a 128k -y "${outputPath}" 2>/dev/null`,
+      { timeout: 15000 }
+    );
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+export function convertOggToMp3OrCopy(inputPath: string, mp3Path: string): string {
+  if (convertOggToMp3(inputPath, mp3Path)) {
+    return mp3Path;
+  }
+  // fallback: keep original OGG
+  fs.copyFileSync(inputPath, mp3Path.replace(/\.mp3$/, ".ogg"));
+  return mp3Path.replace(/\.mp3$/, ".ogg");
+}