Last updated: October 27, 2026
What is bundled
The Audio Trimmer, Audio Joiner, Audio Converter, Audio Speed Changer and Video Trimmer process files in your browser with libav.js version 6.10.9.0 (upstream project: github.com/Yahweasel/libav.js — every file needed is provided on this page), built from FFmpeg 9.0. The Video to GIF Converter uses your browser’s own video decoder and does not use libav.js.
Three unmodified variants from the official v6.10.9.0 release are bundled and loaded only from this website, only when a Media Tool needs them:
- obsolete — audio decoding and encoding: MP3 (LAME), Vorbis, Opus, FLAC and PCM WAV, plus audio filters.
- webcodecs — reading and rewriting MP4 and WebM files without decoding (Video Trimmer fast mode).
- webm-vp9 — VP8/VP9 video and Opus audio decoding and encoding (Video Trimmer accurate mode).
Licence
libav.js and the FFmpeg libraries are licensed under the GNU Lesser General Public License, version 2.1. The bundled build contains no GPL-only components. Each runtime file carries its full licence header, which also covers the third-party libraries compiled into it (Opus, Ogg/Vorbis, LAME, libvpx, emscripten and musl):
- Notices — obsolete variant
- Notices — webcodecs variant
- Notices — webm-vp9 variant
- libav.js licence note and version and checksum list
You may use, study, modify and redistribute this library under the terms of the LGPL-2.1, including replacing the bundled runtime files with your own build.
Complete source code
These archives are the official v6.10.9.0 release’s own sources/ folder, unmodified, hosted on this site. Together they are the complete corresponding source code of the bundled runtime: libav.js itself (including its build scripts and configurations) and every library it was built from.
| Archive | Size | SHA-256 |
|---|---|---|
| emfiberthreads-1.3.tar.gz | 8 KB | 0fe933d7742de3b3213608e0fb087a1ae0d060604d5835f7c9cdfcee0fc8cbcb |
| ffmpeg-9.0.tar.xz | 11.5 MB | 7f607a00dd0d28a729d5a4811205812eef01cf6ef6155025febb6f36a9062d52 |
| lame-3.100.tar.gz | 1.5 MB | ddfe36cab873794038ae2c1210557ad34857a4b6bdc515785d1da9e175b1da1e |
| libaom-03087864.tar.gz | 6.1 MB | 364cc54d1879a0a84b9b78ff5e1f5f04d0a3833e83edc38a10f80c67dc0e0ad3 |
| libav.js.tar.xz | 4.1 MB | ad1932a86ef0bcc87b1e71df34b735f8b3cda0022ffe04b95890adfda24cd186 |
| libogg-1.3.6.tar.xz | 430 KB | 5c8253428e181840cd20d41f3ca16557a9cc04bad4a3d04cce84808677fa1061 |
| libvorbis-1.3.7.tar.xz | 1.1 MB | b33cc4934322bcbf6efcbacf49e3ca01aadbea4114ec9589d1b1e9d20f72954b |
| libvpx-1.16.0.tar.gz | 5.4 MB | 7a479a3c66b9f5d5542a4c6a1b7d3768a983b1e5c14c60a9396edc9b649e015c |
| opus-1.6.1.tar.gz | 10.0 MB | 6ffcb593207be92584df15b32466ed64bbec99109f007c82205f0194572411a1 |
| zlib-1.3.2.tar.gz | 1.4 MB | bb329a0a2cd0274d05519d61c667c062e06990d72e125ee2dfa8de64f0119d16 |
Runtime files
These files are unmodified copies from the release’s dist/ folder. They are served from /assets/js/vendor/libav/.
| File | Size | SHA-256 |
|---|---|---|
libav-6.10.9.0-obsolete.js | 23 KB | 0875c048ea20e715635b63232b50cabcd18a2ff55b17907ecbe5fe2e76a2ddd0 |
libav-6.10.9.0-obsolete.wasm.js | 283 KB | 2f22cf3e708538187cbb58e5bae2b6aad8750624b741f8fb6ac5ae0f3b725a77 |
libav-6.10.9.0-obsolete.wasm.wasm | 2.3 MB | 6a5debf75ee2507a069a2fa7edd664d33789987a7da31254a34cf7743e6878cc |
libav-6.10.9.0-webcodecs.js | 22 KB | b2d82fa6d062c66b12e5279be1c2efa0fd249c9f235b67ad761abf80ff8d66b8 |
libav-6.10.9.0-webcodecs.wasm.js | 266 KB | 0384b73971c917094315aea164fcc27bbf50f42c82a7e2f16000ac9cc4ef4df4 |
libav-6.10.9.0-webcodecs.wasm.wasm | 2.2 MB | 4342db5874e1aff37d078369a19c41e16c123d41714ebf5977ae385ab53b5d3a |
libav-6.10.9.0-webm-vp9.js | 22 KB | ed42e9cb6ca74934637e592a17997abc576efadaa148efb1fe530617dd52513a |
libav-6.10.9.0-webm-vp9.wasm.js | 273 KB | 9b9fc3c4be65df7c84590ef0b17eee59802645c6e7520138889eeedceb6455e9 |
libav-6.10.9.0-webm-vp9.wasm.wasm | 2.9 MB | 9d9b2a033e6e1f99a2cf599b036a30511a6cd5f4628e98bf9ab986d9e50f53dd |
Questions
If a source file is missing or you have a question about these licences, contact hello@toolisco.com.
Questions about this page
If anything here is unclear, email hello@toolisco.com and we’ll be glad to help.