MKV to MP4 converter

MKV files into MP4s that phones, TVs and editors accept — converted on your own device.

One video · processed on your device, nothing is uploaded

No size limit · files are processed on your device and never uploaded · how it works

Honest speed note: video re-encodes at roughly the clip's own length (a 2-minute video takes ~2 minutes). Nothing is uploaded — the work happens on your device.

Advanced settings (optional)

Output options

Format

H.264 MP4 — plays everywhere.

Quality

Hard to tell from the original at normal viewing.

Resolution

Capping the height is the biggest size saver — 720p is plenty for sharing.

Audio

Dropping audio saves space on screen recordings that have none worth keeping.

Runs in your browser. Files are never uploaded — you can go offline after the page loads.

How to use the MKV to MP4

Click “Choose Files” or drop your images into the box above. Whole folders work too.
Adjust the Advanced settings if you need to, then click “Convert”.
When the row shows Done, click “Download” — or “Download all” for a ZIP.

Easy to use

Drop files, pick options, download. Whole folders at once, no signup, no daily limit.

Best quality

The same engines the professionals use — SVGO, resvg, MozJPEG, libwebp, libavif — compiled to run in your browser.

Private & secure

Files are processed on your device and never uploaded. Close the tab and nothing remains anywhere.

This page opens the Video Converter set to MP4. Conversion runs in your browser at roughly the clip’s own length.

This is a pre-set view of the Video Converter. Every option in the toolbar can still be changed.

Frequently asked questions

Why convert MKV at all?

MKV is a fine container with poor support outside desktop players — iPhones, TVs, editors and messengers often refuse it. Repackaged as MP4 the same video plays everywhere.

Other presets

Video ConverterMOV, MKV, AVI and friends into MP4 or WebM that play everywhere Trim VideoWatch the video, mark start and end where you pause it, cut

Your files never leave your device

Most online converters upload your file to a server. InfyTool ships the actual encoders to your browser as WebAssembly instead, so processing happens inside your tab — faster for batches, and nothing to delete afterwards.

No upload, ever. Turn off Wi-Fi after the page loads and every tool keeps working.
No limits. No file-size cap, no queue, no watermark, no account.
Runs on your CPU. Batches use several cores in parallel; nothing is throttled.

More free tools

Need graphics to work with?

InfyTool is built by the same team as these free libraries.

InfyPNGFree transparent PNG graphics for mockups and social posts. InfySVGFree SVG designs and illustrations, ready to optimise or convert. InfyIconFree SVG and PNG icons you can open directly in these tools.