WEBM → M4A · Free · No Upload
Free Online WEBM to M4A Converter — No Installation
Convert WebM to M4A (AAC) right in your browser, in seconds. Free, unlimited, and private: your file never leaves your device.
100% local processing: your file never leaves your device. Once the engine is ready, this tab can keep converting offline. Reopening or reloading offline may not work.
Supported formats:Files .webm up to 500 MB — processed locally · Video and virtually any audio format are also accepted — we extract the audio automatically.
How it works
- 01
Upload the WEBM video
Drag the .webm file to the area above or click to select. Files up to 500 MB are accepted — everything is processed locally.
- 02
The conversion runs in your browser
FFmpeg (the same engine used by professionals) runs in WebAssembly right on the page: the audio track is extracted from the video without sending any bytes to servers.
- 03
Download the M4A
In seconds, the .m4a file is ready for download, in 192 kbps AAC — high quality in a compact file.
Frequently asked questions
Why convert WEBM to M4A?
WebM (VP8/VP9) won't open in Premiere, on the iPhone, or on many TVs — a screen recording made with a web tool needs to become MP4 for editing and sharing; the audio from a YouTube lecture becomes MP3. AAC delivers the same quality as MP3 with about 30% less space — it's MP3's technical successor and the Apple ecosystem standard.
Where do WEBM files come from?
Typically from browser screen recordings (Loom, extensions, MediaRecorder), downloaded YouTube videos and silent videos that replace GIFs on websites. Released by Google in 2010; it's a subset of Matroska limited to VP8/VP9/AV1 with Vorbis/Opus — Chrome's MediaRecorder records to it by default.
Is it worth using M4A?
AAC delivers the same quality as MP3 with about 30% less space — it's MP3's technical successor and the Apple ecosystem standard. MP4 container (brand M4A); typical AAC-LC at 128–256 kbps. Note: an .m4a may contain ALAC (lossless) instead of AAC — same extension, different codecs.
Do I lose quality when converting WEBM to M4A?
There is a re-encoding between two compressed formats, with minimal technical loss — imperceptible for voice and most uses. If you're going to edit the audio multiple times, prefer converting to WAV or FLAC and compress only at the end.
What if I need a transcript of this audio?
After converting, you can transcribe the file with AI on VoxScriber: 30 free minutes per month, with automatic punctuation and speaker identification. Ideal for WhatsApp audio messages, meetings, and interviews.
Is my file sent to any server?
No. All processing is local (FFmpeg compiled to WebAssembly running on the page). The file never leaves your device—it even works offline after the page loads.
Is there a size or quantity limit?
The limit is 500 MB per file (browser memory). There is no limit on the number of uses. For larger files, VoxScriber processes them on the server with uploads up to 5 GB.
Need the text from this audio? Transcribe with AI — 30 min free
Create free account →30 minutes/month free. No credit card required.
Keep exploring
Tools
Convert WEBM to MP3
MP3 is the format that opens on ANY device made since the 1990s — the safe choice for sharing, attaching to email, and playing on your car stereo.
Convert WEBM to WAV
WAV is the WORKING format: lossless editing, accepted by every audio software, and what telephony/IVR systems usually require (8 kHz mono WAV).
Convert WEBM to OGG
OGG compresses well with high quality and is an open, royalty-free format—great for web and games.
Convert MP3 to M4A
Leaving MP3 usually means needing WAV to edit without accumulating loss (recompressing MP3 degrades every generation) or a format required by a specific system — IVR/telephony wants 8 kHz WAV, iPhone ringtones want M4R.
Convert WAV to M4A
WAV takes about 10 MB per minute (16-bit/44.
Convert M4B to M4A
M4B features (chapters, resume-where-you-left-off) only work in Apple apps and dedicated readers — many players won't even open the file.