Audio Converter
Converts audio such as MP3, WAV, FLAC and M4A to OGG (Opus), MP3 or WAV. Add several files at once and compare before and after by ear.
All decoding and encoding happens in your browser. Latest Chrome / Edge recommended.
Formats and quality settings compared
The table below comes from real conversions made with this tool: 30 seconds of music (44.1 kHz stereo, 5,168.0 KiB as WAV) and 26 seconds of speech (mono, 2,242.7 KiB), with the highest frequency still present in each result.
| Format / setting | Music, 30 s | Speech, 26 s | Top frequency kept (music) | Notes |
|---|---|---|---|---|
| WAV (lossless) | 5,625.0 KiB | 2,441.1 KiB | about 21.6 kHz | Editing master; this tool writes 48 kHz |
| MP3 128 / 192 / 320 kbps | 469.1 / 703.7 / 1,172.8 KiB | 407.2 / 610.9 / 1,018.1 KiB | 16.3 / 19.0 / 20.2 kHz | Widest compatibility |
| OGG (Opus) 64 / 96 / 160 kbps | 237.9 / 355.3 / 591.3 KiB | 200.5 / 299.7 / 496.9 KiB | 20.4 kHz (all levels) | Keeps the most treble for the size |
Speech itself only reached about 10 kHz, so OGG at 64 kbps kept the whole voice band. Music is different: MP3 at 128 kbps cut everything above 16.3 kHz. Choose MP3 when you don't know the listener's setup, and OGG (Opus) for a website or app you control.
How to use
- Drop audio files into the window or click to browse. Anything your browser can decode works — MP3, WAV, FLAC, M4A, OGG and more — and you can add several at once.
- Pick a quality level at the top: Low is OGG 64 kbps / MP3 128 kbps, Standard is 96 / 192 kbps and High is 160 / 320 kbps. Each card can use a different output format (OGG, MP3 or WAV).
- Press Convert, listen to the result at the start, middle and end and check both channels, then download. With several files, “Convert all” processes them in order.
Tips by situation
- Sharing meetings and lectures: OGG at 64 kbps shrank our sample to 8.9% of the original while keeping the whole voice band. Try it first when an email attachment is too large.
- Sending music: use MP3 at 192 kbps or more if you don't know the recipient's device. 320 kbps was 1.7 times the size of 192 kbps for 1.2 kHz more treble.
- Editing masters: repeated lossy saves stack up damage. Keep WAV while you work and compress to MP3 or OGG once at the end.
- Game engine assets: this tool's OGG holds the Opus codec, not the Ogg Vorbis listed in Unity's documentation. Export WAV and let the engine compress it.
- Before you send it: play the converted file at the start and at the end. Encoders add short padding, so MP3 came out about 0.03 s longer and OGG about 0.01 s longer, which matters for seamless loops.
Frequently asked questions
Does converting reduce sound quality?
WAV is lossless, so the audio is preserved as is. MP3 and OGG are lossy: they discard the parts we are least sensitive to, and the treble goes first as the bitrate drops. In our measurements MP3 cut above 16.3 kHz at 128 kbps and above 19.0 kHz at 192 kbps, while OGG (Opus) kept up to 20.4 kHz even at 64 kbps. Converting an existing MP3 to WAV or 320 kbps does not bring back what was already removed.
Is there a size or length limit?
We impose no limit, but the browser loads the whole file into memory, so your device's free memory is the practical ceiling. An hour-long recording is usually fine on a computer, while long files may fail on a phone. For constant bitrates you can estimate with size ≈ bitrate × seconds ÷ 8: an hour of OGG at 64 kbps is about 27.5 MiB.
How long does conversion take?
On a PC, converting 30 seconds of music took about 0.2–0.3 s for OGG and about 1.1–1.6 s for MP3. OGG uses the browser's built-in WebCodecs encoder while MP3 runs in JavaScript, which explains the gap. Phones can take several times longer, and you can queue more files while one is converting.
Do some browsers fail to save OGG?
OGG (Opus) output needs WebCodecs, which Chrome and Edge support. Browsers without it show an error message, and you can use MP3 or WAV instead. Input is more relaxed: any format your browser can decode works, though DRM-protected or damaged files will not open.