Compress video without losing quality
Use a light squeeze first: it keeps the original resolution and roughly 60% of the source bitrate. Then check the real size and preview below before you share.
Quick answer: trim first (lossless), remove sound you don't need (lossless), then re-encode at a bitrate that leaves ≥ 0.05 bits per pixel. If that doesn't fit, lower the resolution rather than starving the pixels.
Lossless vs visually lossless
| Change | Picture quality | Size saving | Tool |
|---|---|---|---|
| Trim the start/end | Untouched in kept part* | Proportional to time cut | Trim video |
| Remove sound | Untouched | The audio track (~1 MB/min at 128 kbps) | Remove audio |
| MOV → MP4 repack | Untouched | Little or none | MOV to MP4 |
| Light re-encode | Visually close at good bits/pixel | Depends on the source | Compressor above |
| Lower resolution | Less detail, often invisible on phones | Large | Resize video |
| Newer codec (H.265/AV1) | Similar at lower bitrate | Large, if playable | Codec guide |
*SqueezeVideos re-encodes when trimming so the cut is frame-accurate; at a generous bitrate the difference is not visible.
The rule that predicts quality
File size fixes the bitrate. Divide that bitrate by the number of pixels shown each second and you get bits per pixel. Play with it below: the verdict changes as you trade resolution, frame rate and length.
Where do the megabytes go?
A target size is a fixed pile of bits. Move the sliders and watch the video's share shrink.
3,105 kbps
for the picture, out of 3,333 kbps total (128 kbps audio, ~3% container overhead)
Bits per pixel per frame: 0.025
Tight. Fine for talking heads; game footage will get blocky when the camera moves.
Sharpest safe choice here: 720p at 30 fps.
Questions people ask
Can you compress a video without losing any quality?
Not by re-encoding: every lossy encode discards some detail. Truly lossless size reductions are limited to trimming, removing the sound and repacking (for example MOV to MP4), which copy the picture untouched. Everything else is about making the loss invisible.
What setting matters most for quality?
Bits per pixel: the video bitrate divided by width × height × frame rate. Keep it around 0.05–0.1 for H.264 and the picture stays clean in most footage. If a target size forces it lower, reduce resolution or frame rate rather than starving the original size.
Is H.265 or AV1 better quality at the same size?
Usually yes: they typically need noticeably less bitrate than H.264 for similar quality. Only use them if the person receiving the file can play them; the H.264 vs H.265 page tests your browser.
Why does my compressed video look blocky only in some scenes?
Fast motion, confetti, water and camera shake change most pixels every frame, so they need far more bits than calm scenes. At a fixed target the encoder runs short in exactly those moments.
Should I compress a video that was already compressed?
Avoid it if you can. Each generation adds loss; start from the original recording whenever possible.