ConvertFast

Compress Video Online

Reduce video file size fast with quality presets and optional target size.

Upload Video

Drop video hereChoose VideoUp to 100MB • MP4, MOV, WEBM, AVI
No signup•Secure processing•Auto-deleted after processing

Supported Input and Output

Accepted input
MP4, MOV, AVI, MKV, and WebM video
Output
Compressed MP4 video
Upload limit
Up to 100 MB per video
Controls
Quality preset, Optional target size in MB

What This Processing Changes

Compression re-encodes video with a lower data rate. Stronger compression can reduce size further but may soften fine detail or introduce artifacts.

How to Check the Result

  1. Compare the measured sizes below; already efficient clips may grow.
  2. Watch moving details and listen for audio artifacts.

Limits and Troubleshooting

  • A target size is best effort because duration and visual complexity affect the achievable result.
  • Reduce resolution before using an extreme quality setting when the file is still too large.

Video Compression Intent & Usage

  • Target Size Savings: Compress large video files down to meet email attachment limits or web upload caps.
  • Bitrate Optimization: Intelligently balances video bitrate and quality parameters for efficient storage savings.
  • Combine With Resolution Control: For maximum compression, pair quality presets with a 720p or 480p resolution reduction.

Frequently Asked Questions

How does video compression work?

Video compression optimizes video data by adjusting bitrate and encoding settings to lower file size while preserving acceptable visual quality.

Can I compress video without losing quality?

Moderate compression preserves high visual fidelity. Extreme file reduction may slightly soften details to achieve maximum size savings.

What is the best way to compress video for email or messaging?

Use standard compression or target 720p resolution to bring file sizes under common attachment limits like 25MB.

Are my uploaded videos kept private?

Files are uploaded over HTTPS and processed temporarily. Inputs are removed after processing, and output files are removed after download delivery closes.

Related Video Resolution Tools

Convert Video To 720p720p HD Preset
Convert Video To 1080p1080p Full HD Preset
Change Video ResolutionCustom Resolution Output
Reduce Video SizeTarget File Reduction
Resize VideoWidth & Height Dimensions
Compress VideoShrink Video File Size

Worked Example: Try medium compression on a short synthetic clip.

  1. Upload sample.mp4 from the example below.
  2. Set quality: medium.
  3. Process and download; play the result from beginning to end.

Check Your Download

  • Compare the measured sizes below; already efficient clips may grow.
  • Watch moving details and listen for audio artifacts.

Limit: No fixed saving is guaranteed; source bitrate and duration matter as much as resolution.

Download the example input and repeat the steps above. These are generated test files, not customer uploads.

Input bytes
135,582
Output bytes
104,373
Verified result
640 × 360; 2.020 seconds; h264
Test date
2026-10-06

Measurements apply to this sample and these settings. Other inputs and codec versions can produce different sizes and results.