Can I convert MKV to MP4 without losing quality?

Yes, using a 'container remux' — this rewraps the video without re-encoding. Tools like ffmpeg (-c copy flag) or Handbrake do this in seconds with zero quality loss.

Why does ClipSave download videos as MP4?

MP4 is the most universally compatible format. It works on every device and doesn't require users to install special codecs or players.

What's the difference between a codec and a format?

A format (MP4, MKV) is the container. A codec (H.264, H.265, VP9) is the compression algorithm inside the container. The same codec can be stored in multiple container formats.

Is H.265 better than H.264?

H.265 (HEVC) achieves the same quality at roughly half the file size of H.264. The tradeoff is that older devices don't support H.265 hardware decoding, causing choppy playback.

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Video Formats Explained: MP4, MKV, WebM, AVI and More (2026)

June 26, 2026

Video formats MP4 MKV WebM AVI explained

Why Video Formats Matter for Downloads

When you download a video from the internet, the format it's saved in determines compatibility with your devices, editing software, and streaming services. Understanding the main formats helps you choose the right one for your needs.

MP4 (MPEG-4 Part 14)

MP4 is the universal standard for video distribution. It uses the H.264 or H.265 (HEVC) codec and is compatible with virtually every device, browser, operating system, and video player. Most downloaded videos are MP4.

- Best for: Sharing, watching, editing, uploading - Compatibility: ★★★★★ (everything) - File size: Medium — good compression without major quality loss

MKV (Matroska Video)

MKV is a flexible container format that can hold multiple video streams, audio tracks, and subtitle tracks in a single file. Popular for high-quality movie downloads and anime.

- Best for: High-quality archiving, content with multiple audio/subtitle tracks - Compatibility: ★★★★☆ (not supported natively in all players — needs VLC or conversion) - File size: Varies — often the same as MP4 at equal quality

WebM

WebM is Google's open-source format designed for web video, using the VP8 or VP9 codec. YouTube uses WebM internally. It offers excellent quality at small file sizes.

- Best for: Web streaming, browser playback - Compatibility: ★★★★☆ (all modern browsers, but limited hardware support) - File size: Small — excellent compression

AVI (Audio Video Interleave)

AVI is an older Microsoft format. Files are typically uncompressed or lightly compressed, resulting in large file sizes with excellent quality. Now mostly obsolete for new content.

- Best for: Legacy compatibility, lossless archiving - Compatibility: ★★★☆☆ (limited on mobile devices) - File size: Very large

Which Format Should You Download?

For general use: MP4 (H.264) is the safest choice — plays everywhere, edits in all software. For maximum quality archives: MKV with H.265 codec. For web projects: WebM. For editing: MOV (if you're in the Apple ecosystem) or MP4.

Frequently Asked Questions

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