What is the difference between CBR, VBR, and CRF?

CBR (constant bitrate) forces the same bitrate everywhere — predictable, needed for streaming. VBR (variable bitrate) targets an average size, spending bits where scenes need them — best for hitting exact file sizes via 2-pass encoding. CRF (constant rate factor) targets a quality level and lets size float — best quality-per-byte for files, and the right default for almost everything that isn't streamed.

Should I use CBR or VBR for streaming?

CBR (or capped VBR within platform limits). Twitch, YouTube Live, and RTMP ingest expect a steady pipe — typically 6–8 Mbps for 1080p60 — and spikes get you throttled or dropped. VBR's efficiency doesn't matter live; predictability does.

What is 2-pass encoding and when do I need it?

Two-pass encoding analyzes the whole video first (pass 1), then allocates bits optimally to hit an exact average bitrate (pass 2). You need it only when the final size is fixed — fitting a disc, a 25MB upload cap, or a strict delivery spec. For quality-targeted work, single-pass CRF is as good and twice as fast.

What is capped CRF (CRF with maxrate)?

CRF quality with a bitrate ceiling: the encoder targets your CRF but never exceeds maxrate (with a bufsize buffer). It gives near-CRF quality while guaranteeing player-safe peaks — ideal for self-hosted streaming and Plex libraries where clients choke on spikes but you still want quality-based encoding.

What RF value should I use in HandBrake?

HandBrake's RF is its CRF equivalent: RF 20–22 for H.264 uploads and archiving (lower = better), RF 22–24 for H.265 (which needs higher numbers for the same size). Start at 22 for H.264 / 24 for H.265 and adjust after watching the result on your actual screen.

Does higher bitrate always mean better quality?

Only up to the source's own quality — beyond that you're preserving compression artifacts at great expense (why re-encoded phone footage sometimes grows). And past transparency (visually identical to source), extra bits buy literally nothing visible. Judge by eyes at your CRF/RF, not by megabytes.

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CBR vs VBR vs CRF: Rate Control Explained

Three ways to tell an encoder how to spend bits — one for streams, one for exact sizes, one for everything else. What each does, when each wins, and how they map to HandBrake and FFmpeg settings.

By Hadi Karaki, maker of Formatif — video conversion softwareUpdated September 4, 2026

The three modes in one table

Mode	Controls	Size result	Use for
CBR	Fixed bitrate everywhere	Predictable, often wasteful	Live streaming (Twitch, RTMP)
VBR (2-pass)	Average bitrate target	Exact — hits a size spec	Discs, upload caps, delivery specs
CRF / CQ	Quality target	Floats — optimal per scene	Uploads, archives, everything file-based

Memory hook: CBR serves the pipe, VBR serves the spec, CRF serves your eyes.If there's no live pipe and no fixed size, the answer is CRF — which is why our compression guide never touches anything else for file work.

The hybrids and the app mappings

Capped CRF: quality with a ceiling

CRF plus -maxrate and -bufsize: near-CRF quality with guaranteed player-safe peaks. The right choice for self-hosted streaming and Plex libraries — clients that choke on spikes, quality everywhere else.

HandBrake RF = CRF with another name

RF 20–22 (H.264) or 22–24 (H.265) for quality work; higher for smaller files. Same scale direction as CRF: lower is better and bigger.

NVENC CQP / CQ: CRF for hardware encoders

GPU encoders call it CQP (NVENC/AMF/Quick Sync) or CQ — same constant-quality idea, similar 18–23 sweet spot at 1080p. See our OBS settings guide for CQP in practice.

Why your re-encode got bigger

Bitrate past the source's own quality preserves compression artifacts at great expense. Check source bitrate first (ffprobe) and stay under it — or just trust CRF, which sizes itself to the content.

Rate control FAQs

CBR vs VBR vs CRF?

CBR: fixed bitrate for streams. VBR 2-pass: exact sizes. CRF: quality target for everything file-based.

CBR or VBR for streaming?

CBR (or capped VBR) — 6–8 Mbps for 1080p60. Predictability beats efficiency live.

What is 2-pass encoding?

Analyze first, allocate second — hits exact sizes. Only needed for fixed-size specs; CRF is faster otherwise.

What is capped CRF?

CRF quality with maxrate/bufsize ceiling — best of both for self-hosted streaming and Plex.

What RF in HandBrake?

RF 20–22 (H.264) / 22–24 (H.265) for quality. Lower = better = bigger.

Does higher bitrate mean better quality?

Only up to the source's quality — beyond transparency, extra bits buy nothing visible.

Continue learning

Video Quality & Bitrate →

What bitrate does and why platforms re-compress everything.

H.264 vs H.265 →

The codecs your rate control drives — speed vs size picks.

Right settings, whole folder, no terminal?

Formatif Pro applies quality-targeted encoding across entire folders — offline, with recipes you save and reuse. One-time license, 3-day free trial.

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