Convert Video Files Online: MP4, AVI, MOV, MKV and More

Video format compatibility issues are frustrating — your file won't play on a device, won't upload to a platform, or is too large to share. Here's how to solve these problems.

Most Common Video Formats

**MP4** is the universal standard. Compatible with virtually every device, platform, and media player. Uses H.264 or H.265 codec.

**AVI** is an older Microsoft format. Large file sizes but excellent quality. Limited support on modern devices.

**MOV** is Apple's QuickTime format. Great quality but not always playable on non-Apple devices.

**MKV** (Matroska) is a flexible open-source format. Can contain virtually any codec. Popular for high-quality video archives.

**WebM** is Google's web-optimized format. Designed for HTML5 video, small file sizes.

When to Convert

• **Uploading to social media:** Convert to MP4 (H.264)
• **Editing video:** Convert to a format your editor supports
• **Saving storage:** Convert to HEVC (H.265) or AV1
• **Emailing a clip:** Use a compressed MP4 or WebM
• **Archiving master files:** Keep as ProRes or DNxHD

Step-by-Step Video Conversion

1. Select your video file
2. Choose the output format (MP4 recommended for broadest compatibility)
3. Let ConvertAI process — our FFmpeg engine handles any format pair
4. Download your converted file

Pro Tips

• Always keep an original backup before converting
• For maximum compatibility, use MP4 with H.264 codec
• Reduce file size by lowering the bitrate or resolution
• Batch convert multiple files with our Pro plan

ConvertAI supports all major video formats including MP4, AVI, MKV, MOV, WebM, FLV, and more.