Settings for this task
| Use case | Setting | What to check |
|---|---|---|
| Listening copy | MP3 · 192 kbps | Check the oldest device you need to support. |
| Editing delivery | WAV · required sample rate | Expect larger 16-bit PCM output. |
| Modern compressed audio | Opus or M4A | Confirm codec support in the destination. |
How to use this tool
- Upload a supported audio file and inspect its codec.
- Select the output format, then settings that apply to that format.
- Download and test in the actual receiving application, including tags if important.
Calculated size examples
Calculated, not measured uploads: bytes ≈ bitrate (kb/s) × seconds × 1,000 ÷ 8. MB here means 1,000,000 bytes. Headers, tags and variable bitrate affect actual size. Channels are already included in the total bitrate; do not multiply again.
| Output duration | Format | Bitrate | Estimated audio payload |
|---|---|---|---|
| 5:00 | MP3 | 128 kb/s | 4.8 MB |
| 5:00 | M4A | 192 kb/s | 7.2 MB |
Containers and codecs are different
M4A and OGG are containers, not single quality levels. This implementation encodes AAC in M4A and Opus in OGG, not Vorbis. A program that accepts only Vorbis-in-OGG may therefore reject the OGG download. WMA is accepted as an input by this tool but is not an output option.
Which controls change the result
Bitrate affects lossy outputs such as MP3 and M4A. PCM WAV and AIFF use 16-bit samples here, so bitrate presets do not shrink them. FLAC size depends on the signal and sample configuration. A lossless output label does not guarantee unchanged source bit depth or sample rate, nor recover detail lost in an MP3 input.
Convert once for a clear purpose
If your app already plays the original, conversion may be unnecessary. Each lossy-to-lossy conversion can add artifacts. Preserve the original sample rate unless compatibility requires another; retain stereo when channel placement matters. Compare the output size because changing formats can increase it, particularly when decoding compressed audio to PCM.
Questions about this operation
- Is OGG output Vorbis?
- No, this site writes Opus audio in OGG. Container support and codec support must both match.
- Can I make a WMA file?
- No, WMA is decode-only here. Choose an available output or another application if WMA delivery is required.
- Does FLAC improve an MP3?
- No, it stores the decoded signal without undoing MP3 losses. It may also create a larger file.
- Are metadata and artwork guaranteed?
- No. Preservation is requested when enabled, but fields do not always map between containers.
- Can this repair a corrupt recording?
- Conversion is not a repair guarantee. A missing or unreadable stream may fail before encoding; try re-exporting from its original application.