Compression Estimator

Why bitrate alone tells you nothing

Ask whether 5 Mbps is enough and the only honest answer is another question: for what? At 1280 x 720 and 30 frames a second it is generous. At 3840 x 2160 it is spread across nine times as many pixels and the same footage will fall apart on any complicated motion.

Dividing the bitrate by the pixels it has to describe gives a figure that survives those comparisons. Bits per pixel per frame is the number this tool reports, and it is the closest thing to a single answer about whether a target size is realistic.

Reading the number

These bands are a guide for modern codecs on typical footage, not a rule. Content varies enormously: a static interview shot survives on far less than a handheld street scene at night.

• Below 0.03 is very aggressive. Expect visible blocking whenever anything moves quickly.
• 0.03 to 0.06 is tight. Fine for simple, well-lit scenes with little motion; soft on anything busy.
• 0.06 to 0.12 is a reasonable balance for most material.
• 0.12 to 0.2 is comfortable, and worth it for detailed or fast footage.
• Above 0.2 is generous. The extra size rarely buys anything a viewer will see.

Newer codecs move the bands

H.265 and AV1 generally reach the same visible quality at roughly half to two thirds the bitrate of H.264, so a figure that looks thin in the table above may be fine with a newer codec. The trade is compatibility and encoding time, both of which get worse as the codec gets newer.

What to do when the number is too low

Reducing the resolution is usually the best move. It cuts the pixels the encoder has to describe, which raises the bits available for each one, and a clean smaller picture beats a starved larger one every time. After that, look at the frame rate: halving it from 60 to 30 doubles the bits per frame. Trimming the clip is the bluntest option and often the most effective, because size scales directly with length.