Convert Video Formats for Free

Name: AlphaCut
Brand: AlphaCut
Rating: 4.8 (5798 reviews)

Freely convert between MP4, WebM, MOV, and MKV

Your files are not uploaded to our server. All processing happens on your computer.

Drag and drop your video file here, or click to select

Supports MP4, WebM, MOV, MKV

Your video is not sent externally

Conversion happens 100% in your browser, so no data is sent to our servers.

Ultra-fast Conversion

If the video codec is the same, only the format is changed, allowing even multi-GB files to convert quickly.

Completely Free. No usage limits.

There are no limits on conversion count or file size.

MP4, WebM, MOV, MKV – Convert Freely

You can freely convert between these four formats.

Format guide

Convert video formats with the container and codec in mind

MP4, WebM, MOV, and MKV are containers. H.264, HEVC, VP9, and AV1 are codecs. That distinction matters because changing only the container can be fast and almost lossless, while changing the codec requires the entire video to be encoded again.

AlphaCut's video converter runs in the browser and uses fast conversion when the file structure allows it. If you know the destination platform, editing app, or device before you convert, you can avoid unnecessary re-encoding and preserve more quality.

Which output format should you choose?

MP4 is the safest option when compatibility matters. It works predictably across YouTube, Instagram, TikTok, phones, messaging apps, and most editors. WebM is useful for browser-first publishing, while MOV fits Apple-heavy workflows and some editing pipelines.

MKV is flexible for subtitles and multiple audio tracks, but not every upload destination accepts it directly. For publishing, convert to MP4 first, then compress, trim, or crop the distribution copy if needed.

Fast conversion versus full conversion

Fast conversion changes the container when the existing codec is already compatible. It finishes quickly and avoids visible quality loss because the video stream is not rebuilt.

Full conversion re-encodes the video. It takes longer, but it is the right choice when a file will not open in an editor, does not play on a device, or needs to match a platform's required codec.

Checks before and after conversion

Before converting, confirm the recommended format, maximum file size, and aspect ratio for the destination. If you also need compression, trimming, or cropping, choose the order based on the final deliverable.

Keep the source file untouched and create platform-specific copies. After conversion, review playback, audio sync, color, duration, and file extension before uploading.

Recommended conversion workflow

Confirm the format required by the final platform.
Choose MP4 when broad compatibility is the priority.
Use fast conversion when available to avoid re-encoding.
Check playback and audio sync after converting.
Apply compression, trimming, or cropping only to the output copy.

Tools to use after converting

Video Compressor

Shrink the converted file to meet upload or sharing limits.

Video Trim

Remove unnecessary lead-in or ending footage.

Video Crop

Frame the converted video for vertical, feed, or widescreen output.

FAQ

Is my video file sent externally?

No. The entire conversion process is handled in your browser. Your file is never uploaded to a server.

Are there file size limits?

No. However, since it uses browser memory, processing time for very large files may vary depending on your device's specifications.

Which formats can be converted?

You can freely convert between MP4, WebM, MOV, and MKV. If the video structure is compatible, conversion is fast with no loss in quality.

Why are some conversions fast and others slow?

If the video codec is compatible, only the format needs to be changed, so it finishes quickly. If the structure is different, the video must be re-encoded from scratch, which takes time proportional to its length.

Can I use it on a smartphone?

Yes, it works in mobile browsers. However, for large videos, converting on a PC is faster and more stable.

Want to make Shorts with your converted video?

Upload your converted video. Our AI will pick out the most engaging parts and create clips for Shorts, Reels, and TikTok.