Bitrate or resolution — which matters more?

Low bitrate shows problems first. 720p at a healthy bitrate usually beats 1080p starved of data. On a tight budget, protect bitrate first.

Why is the output bigger than the math?

Container overhead, faststart restructuring and CBR padding all add a few percent; audio bitrate must be counted too. Within ±5% is normal.

Parameters 6 min read

Video Bitrate Chart: Recommended Values by Resolution

Bitrate drives file size and largely drives perceived quality. The right value depends on resolution, frame rate and scene complexity. Ranges below are for H.264; divide by roughly 1.6 for H.265.

H.264 reference ranges

480p @ 30fps: 800–1500 kbps — talking head, lecture archives.
720p @ 30fps: 2000–3500 kbps — everyday sharing, messaging.
1080p @ 30fps: 4000–8000 kbps — general publishing.
1080p @ 60fps: 6000–12000 kbps — gaming, sports.
4K @ 30fps: 18000–35000 kbps — 4K uploads, large screens.
Static screen recordings sit at the low end; fast motion, rain and noise at the high end.

Size math

Size (MB) ≈ total bitrate (kbps) × seconds ÷ 8192. Total = video + audio bitrate (128 kbps AAC; 64–96 kbps is enough for speech). Reverse example: fitting 1080p30 into 100 MB over 10 minutes budgets about 1365 kbps total — below the 1080p floor, so either accept a bigger file or drop to 720p.

CRF or target bitrate

CRF keeps quality constant and lets size float; target bitrate keeps size exact and lets complex scenes degrade. Workflow: compress once at CRF 23, check the size, switch to target bitrate only when a hard cap (25 MB messaging, email attachment) demands it.

Platforms re-encode on upload, so matching their recommended tiers beats massively overshooting them. And files already compressed below ~2 Mbps at 1080p have little healthy headroom left — re-compressing them hurts.