Video converter: MP4, MKV, MOV, AVI, WebM

Online tool for changing the format of video files. Handles MP4, MKV, MOV, AVI, WebM, M4V, TS, FLV, 3GP and WMV, works on several files at once, and tells you up front what will happen to each one: a stream copy or a real re-encode.

How to convert a video

1
Add your videos

Drop one file or many: MP4, WebM, MOV, AVI, MKV, WMV, FLV, TS, 3GP. The conversion runs in your browser through FFmpeg WebAssembly.

2
Pick the output format

Choose the container you need. Each file immediately shows its plan: a stream copy or a real re-encode.

3
Adjust if you want to

Presets change resolution and quality in one click; “Target size” works out the bitrate for the megabytes you ask for.

4
Convert and download

Save each file on its own, or take everything as one ZIP.

Change a video’s format in the browser — copying streams whenever there is nothing to re-encode

⚠️
Drop videos here or click to choose
Several files at once are fine
MP4, WEBM, MOV, MKV, AVI, WMV, FLV, 3GP ·
Files: 0
Format
Preset
Size, MB Bitrate is derived from the size you ask for
Resolution Frame rate
Quality Audio

Features

Lossless container swap
When the source codecs fit the target format, the streams are copied as they are: identical quality, and an MP4 → MKV of a gigabyte file takes seconds instead of minutes.
The plan is shown first
Every file states what will happen to it — copy, audio re-encode, or full re-encode — and roughly how long it will take.
10 output formats
MP4, MKV, MOV, WebM, AVI, M4V, TS, FLV, 3GP and WMV, including the legacy containers older hardware still insists on.
Batch queue
Several files at once, per-file progress, and one ZIP at the end.
Exact file size
“Target size” derives the bitrate from the megabytes you need — for attachment limits and upload caps.
Honest device check
If the CPU lacks the WebAssembly extensions the engine needs, the tool says so up front instead of after a long wait.

FAQ

What does “streams are copied” mean?

It is a container swap with no re-encoding: the video and audio tracks move into the new format byte for byte. Quality does not change at all and the job takes seconds even on large files. It works whenever the target container understands the source codecs — H.264 and AAC, for instance, live equally well in MP4, MOV and MKV.

Why is one file done in a second and another takes minutes?

A second means the streams were copied. Minutes mean a real re-encode, which is needed when the target format cannot carry the source codec (H.264 into WebM, say) or when you changed resolution, frame rate, quality, or asked for a target size.

Are my files uploaded anywhere?

It runs in your browser through FFmpeg WebAssembly — nothing to install, and it keeps working offline once the engine has loaded.

Which format should I pick?

MP4 is the universal one — everything opens it. MKV is the best target for lossless copies because it accepts any codec. MOV suits Apple software. WebM is for the web. AVI, WMV, FLV and 3GP exist for old hardware and software that refuses modern containers.

Why is there no preview for MKV?

Browsers do not play Matroska. The file is perfectly fine — it opens in VLC, MPV, on a TV, or in any ordinary player.

How many files can I convert?

The daily allowance counts FILES, not button presses: converting the same file into another format again during the day is. The live counter sits above the button.

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Who is this tool for?
🎬 Video Creators ✨ Content Creators
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