ToolGPT

Convert MKV to MP4 just by asking

Attach your MKV file, type “Convert this to MP4”, 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.

  • Runs in your browser
  • No sign-in needed
Drop or choose your filesThe assistant opens with your files and does the rest.Choose Files
Things you can type
Open ToolGPTAttach a file and describe what you need.

More about the Video Converter →

How it works

  1. 1

    Attach the MKV

    Open ToolGPT and press the + button beside the message box, or drop the file into the chat. No account is needed to start.

  2. 2

    Ask for MP4

    Type what you need, such as “Convert this to MP4”. Add a resolution, frame rate or bitrate if you have a target in mind.

  3. 3

    Download the MP4

    The result appears as a card in the chat with a download button. Your MKV stays as it was.

Why convert MKV to MP4?

MKV files from screen recorders and downloaded films often will not open on phones, in editing apps or on social sites, which expect MP4. Unless you ask for a new size, frame rate or bitrate, H.264 or HEVC video moves across without re-encoding, while VP9 video and Opus or FLAC sound become H.264 and AAC.

How ToolGPT converts MKV to MP4

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.

About MKV

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.

About MP4

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.

Frequently asked questions

Is my MKV file uploaded?

No. The conversion runs in your browser. Your messages go to the AI assistant, but the video itself is processed on your device.

Can I change the resolution or the file size?

Yes. Ask in the same message, for example “Convert this to MP4 at 720p”. Without a request, ToolGPT keeps the video's own resolution.

Can I convert several MKV files at once?

Yes. Attach them together and ask for MP4. 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.

Open ToolGPT

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