Attach your MP4 file, type “Convert this to MKV”, and ToolGPT does the rest: it reads the video's details, picks the settings and converts it in your browser. You can ask for a smaller resolution or a lower bitrate in the same message.
Open ToolGPT and press the + button beside the message box, or drop the file into the chat. No account is needed to start.
Type what you need, such as “Convert this to MKV”. Add a resolution, frame rate or bitrate if you have a target in mind.
The result appears as a card in the chat with a download button. Your MP4 stays as it was.
MKV is a popular choice for archiving and home media servers because one file can hold several audio tracks, subtitles and chapters. A landscape H.264 MP4 is copied into MKV without loss, but a portrait phone video is re-encoded, because MKV cannot store the rotation flag that MP4 uses.
The conversion runs in your browser. ToolGPT uses the browser's own video encoders where they can do the job and a WebAssembly build of FFmpeg where they cannot, so the video is not uploaded to a server to be converted. The assistant sees only the facts it needs to choose settings, such as the file's length, size and dimensions.
Because your own device does the work, a long or high-resolution video takes longer on an older computer or phone. A progress bar shows how far the job has got, and you can keep chatting while it runs.
MP4 is the standard MPEG-4 video container, used by phones, cameras, streaming sites and editing apps. It usually holds H.264 or HEVC video with AAC sound. Its strength is that it plays almost everywhere; its weakness is that the video is compressed with loss, so each re-encode costs a little quality.
MKV, short for Matroska, is an open container that can hold almost any video and audio codec, several audio tracks, subtitles and chapters in one file. That flexibility makes it popular for films, recordings and home media servers. The downside is patchy support: many phones, editing apps and social sites do not accept MKV.
No. The conversion runs in your browser. Your messages go to the AI assistant, but the video itself is processed on your device.
Yes. Ask in the same message, for example “Convert this to MKV at 720p”. Without a request, ToolGPT keeps the video's own resolution.
Yes. Attach them together and ask for MKV. ToolGPT shows one plan for all of them with a Start button, and each file gets its own result.
Try it with your own file
Open ToolGPT, attach a file, and type what you want done.