Audio & video / Local FFmpeg tool
Create a lossless FLAC copy with a selectable compression level without sending audio away.
The first run loads an approximately 31 MB FFmpeg WebAssembly core from this site. It does not use a CDN or upload your files.
Files are limited to 200 MB total and 20 minutes; mobile devices use an 80 MB limit. Reverse, GIF and boomerang tools have lower duration caps.
At most 60 download files are generated.
Validated downloads will appear here after processing.
Create a lossless FLAC copy with a selectable compression level without sending audio away.
Audio file: sample-1.wav
Compression level = 5Creates a probed and validated .flac (audio/flac). Actual method: FLAC compression levels change encoding effort and file size, not decoded sound quality. Output boundary: Converting a lossy source to FLAC cannot restore detail already discarded.
Choose Audio file sample-1.wav and first confirm that each required audio stream exists.
Use Compression level = 5. The actual FFmpeg rule is: FLAC compression levels change encoding effort and file size, not decoded sound quality.
A download appears only after duration, stream type and .flac container validation. Also check this boundary: Converting a lossy source to FLAC cannot restore detail already discarded.
Local AI / Speech to text
Open-source Whisper Tiny runs in your browser. The file, audio and result are never uploaded.
Choose an audio or video file in the workbench above first.
◎ The model loads only from 321Kit; MiniMax is not called and no transcript history is stored.
How it works
FLAC compression levels change encoding effort and file size, not decoded sound quality.
FLAC compression levels change encoding effort and file size, not decoded sound quality. Processing uses single-thread FFmpeg.wasm. The page does not upload, store or inspect file content outside this device. Cancel, error and page close terminate the worker and revoke temporary object URLs.
Converting a lossy source to FLAC cannot restore detail already discarded. Files are limited to 200 MB total and 20 minutes; mobile devices use an 80 MB limit. Reverse, GIF and boomerang tools have lower duration caps.
Anonymous feedback
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