🎬Video ToolkitAI
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Convert Video Online — Change MP4/MOV/WebM/AVI/MKV Free

Convert between MP4, MOV, WebM, AVI, MKV with H.264 codec by default. Fast server FFmpeg, no watermark, no signup. Supports videos up to 500MB.

MP4MOVWebMAVIMKV
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Drag & drop file here or click to choose

Max 500MB. Supports MP4, MOV, WebM, AVI, MKV

Why use this tool

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5 popular formats

MP4 for mobile, MOV for iPhone, WebM for web, AVI for legacy, MKV for HD archival.

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Quality vs Speed toggle

Pick 'High quality' (CRF 18) or 'Fast' (CRF 23 + fast preset). Use-case dependent.

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Safe server FFmpeg

Processed on server, files auto-delete after 60 min. Never uploaded to 3rd-party cloud.

How to use

  1. 1Upload video in any format.
  2. 2Pick output: MP4/MOV/WebM/AVI/MKV.
  3. 3Pick quality: high or fast.
  4. 4Click Convert. Download.

Video convert — when?

Each format has trade-offs: MP4 (H.264 + AAC) universal, every device/browser supports. MOV for iPhone/QuickTime. WebM (VP9) for web embeds (20-40% smaller than MP4). AVI for legacy Windows. MKV for HD archival with multi-track audio/subs.

Tool uses FFmpeg libx264 (H.264) as default video codec. WebM uses libvpx-vp9. Audio AAC 128kbps default, good enough for music + voice.

  • ✓MP4/MOV/WebM/AVI/MKV bidirectional
  • ✓H.264 + AAC default
  • ✓VP9 for WebM
  • ✓CRF 18 (high) or 23 (fast)
  • ✓Preserves audio
  • ✓Server FFmpeg
  • ✓No watermark

FAQ

MP4 vs MOV difference?

Same H.264 + AAC container, different metadata. MOV is Apple's wrapper. Everything plays MP4 but MOV is best on iOS/Mac.

Is WebM really smaller than MP4?

Yes, VP9 compresses 20-40% better than H.264 at same quality. Downside: not all tools support, prefer for web embeds.

Does convert preserve subtitles?

Phase 1 no. Subs stripped. Phase 2 will add preserve subtitle stream option.