Audio Converter

Convert many audio files at once to MP3, WAV, Opus or M4A, then download them one by one or as a ZIP. Files are converted by your browser and never uploaded.

Add files
Choose the format and convert
Download

Drop audio files here or click to choose them

MP3, WAV, OGG, Opus, M4A, AAC, FLAC, WebM, and videos (MP4, MOV, MKV) · several at once · processed only on your device

Output

Format

Bitrate

Sample rate

Mono (one channel)

About the Audio Converter

This free audio converter changes the format of many files in one go: FLAC to MP3 for a car stereo, WAV to MP3 to save space, M4A from an iPhone to MP3, or MP3 to WAV for editing software. Add your files, choose the output format and click Convert. Your browser does all the work: the files never leave your device.

It reads MP3, WAV, OGG Vorbis, Opus, M4A / AAC, FLAC and WebM audio, and can also take the sound of MP4, MOV, WebM or MKV videos.

Key Features

Batch conversion: a queue with the status and progress of each file; files are processed one after the other to keep memory use low.
Output formats: MP3 from 128 to 320 kbit/s, WAV 16 or 24 bit, Opus from 64 to 192 kbit/s and M4A (AAC) when the browser supports it.
Options: sample rate (48 kHz, 44.1 kHz, 22.05 kHz, 16 kHz…) and mono mix.
Download: each file with its own button, or all of them in a single ZIP file.

How to Use the Tool

Step 1: drop your files on the area above or click to choose them (you can select several at once).
Step 2: choose the format, the bitrate and, if needed, the sample rate and mono.
Step 3: click “Convert”; follow the progress in the list, and stop at any time.
Step 4: download each file with ⬇️, or everything with “Download all (ZIP)”.

Common Use Cases

Convert an album of FLAC files to MP3 for a phone, a car or an old music player.
Turn voice memos (M4A) into MP3 to send them by email or upload them to a website.
Prepare WAV files at 44.1 kHz or 48 kHz for a video or audio editing project.
Shrink podcast or lecture recordings with Opus or mono MP3 at a low bitrate.

Tips & Best Practices

Which bitrate? 192 kbit/s MP3 is transparent for most listeners; 128 kbit/s is enough for speech; 320 kbit/s for archiving music in MP3.
Quality cannot be added back: converting an MP3 to WAV or to 320 kbit/s makes a bigger file, not a better one. Convert from the original (FLAC, WAV) whenever possible.
M4A (AAC) encoding depends on the browser (usually available in Chrome and Edge on Windows and macOS, and in Safari); otherwise the option is disabled. Opus always outputs 48 kHz.
Large batches: converted files are kept in memory until you close the page; the ZIP is limited to 2 GB.

Privacy & Security

Your files are read and converted only in your browser: they are never uploaded, stored or analysed on a server, and the tool sends no data over the network. Reading and writing audio files relies on Mediabunny 1.62.1 (Mozilla Public License 2.0), MP3 encoding on lamejs 1.2.1 (LGPL), both served from this site.