Is this MP4 to MP3 converter really free?

Yes. Up to 5 files at a time, no signup, no catch. The free tier adds a small watermark to image output — Pro ($9.99/mo or $49/yr) removes it, raises the file size limit to 500 MB, and unlocks unlimited batch conversion.

Are my files uploaded to a server?

No — and you can verify it yourself. Open DevTools → Network tab, then convert a file. You'll see zero upload requests. Everything runs right in your browser. We never see your files.

How long does conversion take?

Usually 1–3 seconds for a typical file. The very first conversion on a fresh page load may take 5–20 seconds while the converter engine loads — after that it's instant. Your CPU does all the work locally.

What is the file size limit?

Free: up to 10 MB per file, 5 files per batch. Pro: up to 500 MB per file, unlimited batch. If you're working with large videos or RAW photos, Pro is built for that.

Can I batch convert multiple MP4 files at once?

Yes — drop multiple files at once (or Ctrl/Cmd+click to select them) and they all convert in parallel. Free accounts handle up to 5 files per batch; Pro has no limit.

What bitrate will the converted audio use?

We default to 192 kbps for MP3, 128 kbps for OGG/Opus, and 320 kbps for M4A/AAC. These settings are perceptually transparent — most listeners can't tell the difference in a blind test.

Will my metadata (ID3 tags, album art) be preserved?

Yes, when both formats support it. Tags carry over on conversions like MP3→M4A or FLAC→MP3. WAV has limited tag support, so some metadata may not transfer.

Does the converter re-encode the video?

No — we extract only the audio stream and encode it as MP3. The video track is discarded. This is fast and doesn't reduce the audio quality beyond the MP3 encoding step.

Can I convert any video format to MP3 this way?

This converter accepts MP4 files specifically. For MOV, MKV, AVI, or WebM files, use the corresponding video converter page and select MP3 as the output.

How private is this converter?

Completely private — by design, not policy. There is no upload endpoint. Files are processed right inside your browser tab and disappear the moment you close it. We collect only anonymous page-view counts; your file content is never seen or stored.

MP4 to MP3 Converter — Free, Extract Audio Online

How to convert MP4 to MP3 online

1
Drop your MP4 file
Drag and drop your MPEG-4 Part 14 file onto the converter, or click to browse your files. You can select up to 5 at once. Nothing leaves your device — conversion happens right here in the browser.
2
Hit Convert — it happens locally
Click Convert and watch it go. There's no upload, no server queue, no waiting. The converter runs MPEG-4 Part 14 → MPEG-1 Audio Layer III entirely in your browser tab. Most files finish in 1–3 seconds.
3
Download your MP3
Your MPEG-1 Audio Layer III file is ready. Click Download, or grab a ZIP if you converted a batch. Close the tab and everything disappears — no copies kept anywhere.

MP4 vs MP3: format overview

MP4

MPEG-4 Part 14

Moving Picture Experts Group · 2001

Compression: lossy
Transparency: No

✓ Universal compatibility across all platforms
✓ Excellent compression with H.264/H.265
✗ H.264 has royalty implications

MP3

MPEG-1 Audio Layer III

Fraunhofer Society · 1993

Compression: lossy
Transparency: No

✓ Universal compatibility — plays everywhere
✓ Good compression at 128–320 kbps

MP4 magic bytes: 00 00 00 xx 66 74 79 70

MP3 magic bytes: 49 44 33 (ID3) / FF FB

Why convert MP4 to MP3?

MP4 video files contain both a video track and one or more audio tracks, but sometimes the video component is entirely unnecessary. Podcast recordings captured through screen recording software like OBS Studio, interview sessions from Zoom or Google Meet exports, YouTube music videos saved offline, and lecture recordings from course platforms all share this trait: the audio is what matters, and the video track adds file size for no benefit. A one-hour lecture MP4 might be 500 megabytes; the extracted audio as MP3 might be 60 megabytes.

MP3 is universally compatible with every audio player ever made. iTunes, Spotify local files, VLC, Windows Media Player, Winamp, car stereo Bluetooth, Amazon Echo, and virtually every podcast hosting platform including Buzzsprout and Anchor accept MP3. When you need to edit interview audio in Audacity, load a track into GarageBand, or submit a recording to a voice casting platform, MP3 is almost always the expected input format.

Extracting audio from MP4 to MP3 is a lossless operation in the sense that the audio quality from the original video track is preserved at whatever bitrate you choose. A 192 kbps MP3 is indistinguishable from higher bitrates for most spoken content, and 128 kbps is sufficient for podcasts and voice recordings. For music, 320 kbps preserves full fidelity. The conversion is fast because no video encoding is required, and the output file is immediately ready for playback, editing, or distribution.

Quality & file size: MP4 to MP3

Typical file sizes: MP4 100–300 MB → MP3 3–5 MB.

Both MP4 and MP3 use lossy compression. We transcode at high quality settings (equivalent to MP3's recommended web quality) to minimize generational loss.

Color depth: MP4 supports standard color, MP3 supports standard color.

Transparency: MP4 does not support transparency. MP3 does not support transparency — transparent areas become solid white.

Frequently asked questions

Privacy: how FormatDrop handles your files

Your MP4 files are converted 100% inside your browser. They are never uploaded to our servers, never stored, and never seen by anyone other than you. This isn't a privacy policy claim — it's an architectural guarantee: our server has no endpoint that receives file bytes.