Video tools
Remux video containers (MP4, MOV, MKV, WebM) - lossless, locally in the browser, no upload.
The video tools cover both: lossless repackaging between the MP4, MOV, MKV and WebM containers without re-encoding the picture, and - where you actually want to change the file size or format - real re-encoding to compress, convert or turn into a GIF.
As with the audio tools, ffmpeg runs as WebAssembly locally in your browser. Your video is never uploaded to a server; the entire processing happens on your device, without an account and without an upload limit.
Convert
Remux video
Swap the video container (MP4, MOV, MKV, WebM) locally - no re-encoding, lossless and no upload.
ASS to SRT
Convert an ASS/SSA subtitle file to the simple SRT format locally - timings and text stay, style tags are dropped. No upload.
SRT to ASS
Convert an SRT subtitle file to the ASS/SSA format locally - with a valid default style as a starting point. No upload.
Video to GIF
Turn a video into an animated GIF locally in your browser - pick the width and frame rate. The video never leaves your device. No upload.
Tools
Convert SRT to VTT
Convert an SRT subtitle file to WebVTT, the format HTML5 video needs, locally in your browser. The file never leaves your device. No upload.
Convert VTT to SRT
Convert a WebVTT subtitle file to the widely supported SRT format that every player understands, locally in your browser. Nothing is uploaded.
Subtitle to text
Extract the plain text from an SRT or VTT subtitle file locally in your browser - without timestamps, as a clean transcript. No upload.
Compress video
Compress a video to a smaller file locally in your browser - choose resolution and quality. The video never leaves your device. No upload.
Convert video
Convert a video between MP4 and WebM locally in your browser - using your browser codecs. The video never leaves your device. No upload.
Analyze a media file
Read the container, codec, duration, resolution, frame rate and audio track of a video or audio file - locally in your browser. No upload.