tooloora

Convert Audio — MP3, WAV, M4A, OGG & FLAC in your browser

Convert single files or a whole batch, pick the MP3 bitrate yourself — processed locally, nothing is uploaded.

Runs locally — nothing is uploaded

Drop audio files here or click

MP3, WAV, M4A, OGG or FLAC · several files possible · stays local

Runs locally in your browser – no upload.

Convert audio — right in your browser

Drop your files, pick a target format and, for MP3, the bitrate, then download the result — as a single file or as a ZIP. The conversion runs entirely in your browser: nothing is uploaded, there is no queue, no signup and no server-side size limit. Just MP3, WAV, M4A, OGG and FLAC.

Which format do I need?

  • MP3 is the lowest common denominator: it plays in every car stereo, on every phone and in every presentation tool. Pick it when you do not know what the recipient can open.
  • WAV is uncompressed and therefore lossless, but large — the right choice when the file goes into an editing program next.
  • M4A (AAC) usually sounds better than MP3 at the same bitrate and is the default in the Apple world.
  • OGG (Opus) is remarkably efficient at low bitrates and the first choice for speech on the web.
  • FLAC compresses losslessly — according to Xiph.Org's official FLAC documentation typically to 50 to 70 percent of the original size, with identical sound.

Which MP3 bitrate is right?

Do the maths yourself: bitrate divided by 8 gives bytes per second. At 192 kbit/s that is 24,000 bytes per second, so about 1.44 MB per minute — a good default for music. 128 kbit/s (roughly 0.96 MB per minute) is enough for speech and podcasts, and 320 kbit/s (about 2.4 MB per minute) squeezes the maximum out of the format, which you will only hear on good headphones.

Does converting improve quality?

No — and knowing this saves a lot of disappointment. Converting an MP3 to WAV makes the file bigger, not better: what the first compression discarded is gone for good. Going from one lossy format to another (MP3 to M4A) even adds a second round of loss. Always start from the highest-quality source you have.

Honest limits

  • Not every device can write every format. MP3 and WAV always work — MP3 through a bundled LAME WebAssembly encoder, WAV as uncompressed PCM. AAC, Opus and FLAC need your browser's encoders; if they are missing, the button is greyed out instead of the job failing after the click.
  • Up to 30 minutes per file. For conversion the audio is fully decoded and lives in memory: roughly 21 MB per stereo minute at 44.1 kHz.
  • Metadata and cover art are not carried over when re-encoding. Set title, artist and artwork again in your music app afterwards.

Frequently asked questions

Are my audio files uploaded to a server?

No. Decoding and encoding run entirely in your browser; the files never leave your device. The MP3 encoder is a WebAssembly build of LAME served from this site, so no third-party CDN is contacted either.

Which MP3 bitrate should I pick?

192 kbit/s is a good default for music: 192 000 bits per second divided by 8 is 24 000 bytes per second, so one minute needs about 1.44 MB. Choose 128 kbit/s for speech and podcasts (about 0.96 MB per minute) and 320 kbit/s when you want the maximum MP3 quality.

Why are some target formats greyed out?

AAC, Opus and FLAC are encoded with your browser's own encoders (WebCodecs), and not every browser ships all of them. The tool probes what your device can actually do and disables the rest instead of failing after you click. MP3 and WAV always work.

Does converting improve quality?

No. Converting MP3 to WAV makes the file bigger, not better — quality lost in the first compression is gone for good. Converting from one lossy format to another (MP3 to M4A) adds a second round of loss. Start from the highest-quality source you have.

How long may a file be?

Up to 30 minutes. Decoded audio needs about 21 MB of memory per stereo minute at 44.1 kHz, so a 30-minute track already occupies roughly 635 MB while it is being processed. Longer recordings are better cut into parts first.