mp3
The most compatible choice for sharing, downloads, cars, phones, and older players. Start at 128–192 kbps for music.
Fast, private audio compression
Audio Compressor
Reduce audio file size. Choose from optimized presets, adjust quality, or target a specific file size.
Files stay in your browserMediaBunny Web WorkersBatch compression
Step 1
Add your audio
Drag files here, browse your device, or add several files for batch compression.
Drop audio files here or click to browse
MP3, WAV, FLAC, AAC, OGG — up to 500MB
Step 2
Choose compression settings
Start with a use-case preset, then adjust quality, target size, or advanced output options.
Use-case Presets
70%
Smaller fileBetter quality
Estimated bitrate
229 kbps
Bitrate Reference
16
32
64
96
128
192
256
320
VoicePodcastMusicAudiophile
Audio is processed locally in your browser and is never uploaded.
Continue your workflow
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Pull the audio track from any video file. Choose from multiple audio tracks and convert to MP3, WAV, or AAC.
Audio Trimmer
Trim MP3, WAV, FLAC, AAC, M4A, OGG, and Opus audio online. Select an exact time range with a visual waveform, preview the cut, and export locally.
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Formats, workflow & privacy
Compress MP3, AAC, M4A, Opus and OGG audio online
Reduce audio file size by choosing a practical bitrate for the destination. The compressor supports batch processing, live size estimates, browser previews, and local downloads.
aac
Efficient lossy audio for mobile playback and Apple devices when you want a smaller file at a similar quality.
m4a
AAC in an MP4 container, useful for iPhone, macOS, and modern media players that prefer M4A files.
opus
A modern, efficient format for voice, web apps, streaming, and low-bandwidth delivery.
ogg
An open audio container commonly used by games, Linux applications, and web projects.
How to compress an audio file
No account or upload is required. Choose a sensible preset, check the estimated output, and download the local result.
- 01
Select your files
Drop MP3, WAV, FLAC, AAC, M4A, OGG, Opus, and other supported audio files into the tool. Multiple files can be added at once.
- 02
Choose quality or target size
Use a podcast, music, voice memo, or ringtone preset. For a hard upload limit, switch to Target Size and set the maximum in megabytes.
- 03
Compress, preview and download
Start processing in a local Web Worker, listen to completed results in the browser, then download one file or the whole batch as a ZIP.
Common audio compression scenarios
The right settings depend on how the audio will be used. These starting points help you reduce size without wasting quality.
Email and messaging
Use MP3 or M4A at 96–160 kbps for voice notes, interviews, and everyday sharing when attachment limits matter.
Podcasts and spoken audio
Choose the Podcast preset or 64–128 kbps mono audio. Speech remains clear while downloads and storage become much smaller.
Music for portable listening
Start at 192 kbps for a balanced MP3 or AAC export. Keep the original FLAC or WAV master instead of recompressing it later.
Audio for video projects
Compress a delivery copy for review or upload, but keep a lossless source for editing, mixing, and future exports.
Private by design
Files are read by your browser and processed in local MediaBunny Web Workers. They are not sent to a MediaKit server. When you remove files or close the tab, the browser can release the local object URLs and worker resources.
FAQ
Audio compressor FAQ
Are my audio files uploaded?
No. Compression runs in your browser. The selected files are passed to local Web Workers and are not uploaded to MediaKit.
Which audio formats can I compress?
You can add MP3, WAV, FLAC, AAC, M4A, OGG, Opus, WMA, AIFF, AC3, E-AC-3, and PCM files. Output options include MP3, AAC, M4A, Opus, and OGG when the browser supports the required codec.
What bitrate should I choose?
For music, 128–192 kbps is a practical starting point and 256–320 kbps keeps more detail. Spoken audio often works well at 64–128 kbps, especially in mono. Higher bitrate means a larger file.
Can I compress an MP3 again?
Yes, but it is another lossy encode and may add audible artifacts. If possible, return to the original WAV or FLAC and create a fresh delivery copy.
Does it work on phones?
Yes, on a current browser. Keep the tab open while encoding and use smaller batches when device memory is limited.
How large can an audio file be?
Each input can be up to 500 MB. Actual processing time and the number of files you can process at once also depend on available device memory.
Keep working
Related audio tools and tutorials
Convert audio to another format
Choose MP3, AAC, FLAC, WAV, Opus, or OGG when the destination requires a different format as well as a smaller file.
Open the toolTrim silence before compressing
Remove dead air or unwanted sections first. Cutting duration often saves more space than lowering bitrate alone.
Open the tool