Free online MP4-to-MKV converter — upload a MP4 file and download a MKV. Fast, private, no signup.
Drag and drop your MP4 into the converter above, or click to choose it. Large files upload straight to storage with a progress bar — and we detect the real format from the file's bytes, so even a mislabeled file works.
MKV is already selected as the target. Any options that apply to a MKV — quality, resize, rotate and more — appear automatically; tweak them or leave the defaults, then start the conversion.
Your MKV is ready in seconds. Download it, inspect or strip its metadata, or share it with a private link — your choice.
Drop your MP4 file into the converter above — we auto-detect the real format from its bytes, convert it, and give you a MKV to download. No software to install.
Yes. Convert MP4 to MKV for free right in your browser, with no account needed to get started.
Your file is transferred over an encrypted connection and anonymous uploads are temporary. You can also view and strip metadata (location, device, author) before you download.
MPEG-4 video container; the web/mobile default. Matroska open multimedia container.
Convert MP4 to: MOV · WEBM · 3GP · AVI · FLV · MPEG · OGV · TS · WMV · JPG
Convert to MKV from: 3GP · AVI · F4V · FLV · M2TS · M2V · MOV · MPEG · MTS · MXF