Parameters 7 min read
Video CRF Explained: Constant Quality vs Bitrate Mode
CRF (Constant Rate Factor) tells the encoder "keep this quality level, spend whatever bitrate it takes". Target bitrate says "spend exactly this much, quality varies". For archiving and general compression, CRF is almost always the right choice.
The H.264 scale in practice
- 18: visually transparent for most footage — archive tier.
- 20–23: excellent for 1080p uploads and general sharing.
- 24–26: screen content, tutorials and talking heads — high-compression material.
- 27+: storage-constrained archives; test on your content before batch converting.
CRF vs target bitrate
Use CRF when quality matters and final size can float (archives, uploads with generous caps). Use target bitrate when the size is a hard constraint (25 MB WeChat limit, platform upload caps). CRF output size varies wildly with content: static scenes cost almost nothing, fireworks cost a fortune — that is the point.