FormatOwl.
Credits & pricing

Compress audio

Reduce audio size by adjusting bitrate, sample rate and channels. Upload MP3, WAV, AAC, M4A, FLAC or OGG and export MP3 or M4A.

01

Upload

Drop your files here

MP3 · WAV · AAC · M4A · FLAC · OGG

Up to 20 files per batch · 1.0 GB per file

02

Settings

Compression preset

Automatic settings do not raise the sample rate. Mono and stereo are retained; surround audio is mixed to stereo. A listening copy is provided for incompatible inputs.

Estimated cost: Choose a file to estimateRemaining —
Indicative estimate · Full price unverified

Based on size, duration, pixels, pages and settings. Batches show a total. ≈ is indicative; + means only part of the cost is included. The server quote after analysis takes precedence.

Resource budgets are not verified prices. Confirm a maximum before paid processing; unused reservations are returned.

View credits and billing rules

Private files. Automatically deleted after 24 hours, or delete them whenever you like.

Formats and limits

Input
MP3 · WAV · AAC · M4A · FLAC · OGG
Output
MP3 · M4A (AAC)

Up to 1 GiB per file and 20 files per batch.

How to use this tool

  1. Choose up to 20 supported files. Every file in the batch uses the same settings.
  2. Adjust the settings and start processing. Keep the page open until uploading finishes.
  3. Preview the results, download individual files, or create a ZIP of successful results.

Settings and results

Try 192 kbps for a starting comparison, 128 kbps for a smaller file, or 64 kbps when size matters more than detail. Listen to speech and music separately. Actual AAC bitrate varies.

File storage and deletion

Files are uploaded and processed on the server. Originals and results are stored privately and accessed through their account or browser session; downloads use short-lived links. By default, files expire 24 hours after upload and are removed by the cleanup process. You can delete them earlier in your workspace. The current local default allowance is 20 uploaded files per 24 hours.

Read the usage and data guide

Common questions

Can compressed audio become larger?

Yes. An already low-bitrate input can be smaller than the selected output. FormatOwl still exports your chosen format and reports a larger result.

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