How do I convert MOV to MKV?

Upload your video, select MKV as output, adjust optional quality and bitrate settings, then convert and download.

Is MOV to MKV conversion free?

MOV to MKV conversion is free for standard usage on WebioTools.

Can I control output quality and size?

Yes. You can adjust CRF quality, bitrate, FPS, and resolution to balance output quality, compatibility, and file size.

MOV to MKV Converter

Convert MOV to MKV online

Upload video

Click to upload or drag and drop

MP4, AVI, MOV, WebM, MKV, FLV, WMV up to 25MB

Free online video converter

Convert MOV to MKV online

You can upload videos up to 25MB. Preview your clip, pick a format and optional quality settings, then start conversion. Longer videos and higher quality settings usually take more time because the file is sent securely to our servers, converted, and sent back for you to download. Your files are processed for conversion and are not kept after the job completes.

Typical uses

Export MP4 for maximum compatibility
Produce WebM for the web
Downscale resolution or FPS to reduce file size

How to convert video (3 steps)

Upload
Add a video; metadata (resolution, fps, duration) loads when possible. Preview the original before you convert.
Configure
Pick MP4, AVI, MOV, WebM, MKV, FLV, or WMV. Open advanced settings for CRF, bitrate, resolution, and FPS. Click Convert and wait for the progress bar.
Download
Preview the output, compare file size, then download the converted video to your phone or computer in the format you chose (for example MP4 or WebM).

Common questions

Why does conversion take a long time?

Your video is uploaded, converted on our servers, and then returned for download—so length, resolution, and quality settings all affect wait time. If a conversion seems stuck, try a shorter clip, a smaller resolution, or a lower bitrate and convert again.

Why did my download disappear?

Changing format, quality, bitrate, resolution, or FPS clears the last output so you don't save mismatched settings. Run Convert again.

What is CRF?

Constant Rate Factor: lower values mean higher quality and larger files for codecs that use it. Pair with bitrate and resolution for predictable results.

Quick tips

Reliable uploads

Use a stable Wi‑Fi or wired connection for large files. Keep this tab open while converting and avoid refreshing the page until the progress bar finishes.

Smaller files

Lower resolution and fps before you slash bitrate—big dimension changes often save more than CRF tweaks alone.

Shortcuts

On a keyboard, use Ctrl+Enter (or ⌘+Enter on Mac) to start conversion, and Esc to clear and start over. Shortcuts are ignored while you are typing in a box.