Video Compressor
Reduce video file size online for free — MP4, MOV, AVI, MKV, WebM and more. Compress for WhatsApp, email, YouTube or Instagram. No watermark, no sign-up.
Frequently Asked Questions
How do I compress a video without losing quality?
How do I compress a video to send via email?
How do I compress a video for WhatsApp?
How do I reduce video file size for Instagram or TikTok?
What settings should I use to compress a video for YouTube?
How much will my video be compressed?
How do I compress an iPhone video (HEVC/H.265)?
Will compressing a video affect the audio?
What is the difference between the quality settings?
What video formats are supported?
Is the video compressor free? Is there a watermark?
Is my video private and secure?
Why is my compressed video larger than the original?
Compress Video for Any Platform
Every platform has a different file size limit. Use these recommended settings to hit the right size first time.
Medium quality at 480p keeps files under 16 MB — the WhatsApp video send limit.
Most email providers cap attachments at 25 MB. Medium + 720p usually hits 10–20 MB.
Instagram Reels allow up to 100 MB. High quality at 1080p keeps it crisp.
YouTube re-encodes uploads, so High quality at 1080p preserves detail through their processing.
Discord free accounts allow 25 MB uploads. Low quality at 480p easily fits short clips.
Compressing videos before cloud backup can cut storage use by 50–80% with minimal quality loss.
How Video Compression Works
Video files are large because they store hundreds of frames per second. Our compressor uses H.264 (libx264) encoding with Constant Rate Factor (CRF) to intelligently discard data that is least visible to the human eye — reducing file size while keeping the video looking sharp.
CRF compression is different from fixed bitrate: instead of a constant data rate, it allocates more data to complex scenes (motion, detail) and less to static or simple scenes. The result is better quality per byte than older methods like video size calculators or simple bitrate reduction.
The output is always an MP4 file with H.264 video and AAC audio — the most
universally compatible format, supported by every phone, browser, TV, and editing app.
The +faststart flag is also applied, so compressed videos begin playing
immediately when shared online without needing to fully download first.
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