How It Works

Drop your audio, pick a preset or a target size, and get a smaller, cleaner file — converted entirely on your device.

1

Drop Your Files

Drag in any number of audio files — even multi-hour recordings. Nothing uploads; files are read directly from your computer.

2

Pick a Preset or a Target Size

Podcast, Voice Memo, Music, Audiobook, Lossless Archive — or type "fit under 100 MB" and let the math work it out. Fine-tune format, loudness, silence trimming, and channels per file.

3

Convert on Your Device

The audio engine runs locally, often faster than realtime, while the app stays smooth and responsive. A one-time download the first time you use it; fully offline after that.

4

Save Everything

Save All streams every finished file straight to a folder you pick, or download them individually — no server round-trip either way.

Privacy Guarantee

  • All conversion happens locally in your browser — zero data leaves your machine
  • Network is only used to download the audio engine on first use (then cached locally)
  • Disconnect your internet after that — the app works entirely offline

What You Can Do

  • Formats: MP3, M4A/AAC, Opus, OGG, WAV, FLAC — in and out
  • Target size: "fit under 100 MB" solved automatically
  • Loudness: EBU R128 normalization for podcasts and music
  • Cleanup: silence trimming, mono downmix, sample-rate conversion

Frequently Asked Questions

Is my audio uploaded anywhere? +
No. Every conversion runs entirely on your device, inside your browser. Your files never leave your machine. You can verify this yourself: disconnect your internet after the one-time engine download and the app keeps working.
What audio formats are supported? +
MP3, M4A/AAC, Opus, OGG, WAV, and FLAC — both in and out. You can also drop a video file and extract just its audio track.
Can I make a file fit a specific size, like under 100 MB? +
Yes. Target-size mode calculates the exact bitrate needed for your file's duration and format, warns you if that bitrate would sound bad, and automatically corrects if the first pass lands slightly over your target.
Does it handle multi-hour files? +
Yes. Files are read directly from disk without copying the whole thing into memory, and very large or long files are processed in segments so the app stays within safe memory limits.
What is loudness normalization? +
It adjusts your file's overall volume to a broadcast-standard level (EBU R128), so your podcast or track doesn't sound quieter or louder than everyone else's. We measure your audio first, then apply a single clean gain adjustment — no audible pumping.
Do I need to download anything every time? +
The audio engine downloads once (a one-time download of a few megabytes) and is cached in your browser. Every visit after that starts instantly and works fully offline.