Video File Size from Bitrate Estimator

Estimating video bitrate by resolution and codec

For a quick estimate, use size_MB = bitrate_Mbps · duration_s / 8. On YouTube the recommended H.264 bitrates run 8 Mbps at 1080p, 16 Mbps at 1440p, and 35–45 Mbps at 4K. H.265 (HEVC) hits the same perceived quality at roughly half that, and AV1 shaves off another ~30% on top of HEVC. CRF (Constant Rate Factor) lets you set quality directly, and for H.264 anything from 18 to 23 looks visually lossless. Live platforms cap things too: Twitch tops out at 6 Mbps for 1080p60. So a 30-min 1080p H.264 clip at 8 Mbps comes to 8 · 1800 / 8 = 1800 MB ≈ 1.8 GB.

Applications: production, streaming and OTT

Editors lean on this inside Premiere, DaVinci Resolve, and Final Cut when they're planning export targets. Livestreamers use it to set a CBR that fits their upload bandwidth, and online educators reach for it while producing video lessons. OTT services like Netflix, Disney+, and Prime Video ship a whole bitrate ladder so adaptive streaming (ABR) can switch quality on the fly depending on the viewer's connection.

FAQ

H.264 or H.265? H.265 cuts bitrate by about half, but it's slower to encode and browsers don't play it back as reliably. If compatibility matters, H.264 is still the safe pick.

What changes between 30fps and 60fps? When you double the framerate, plan on bumping the bitrate target up by about 50% to hold the same quality.

Why does my exported file exceed the estimate? The audio track, container overhead, and VBR peaks each tack on a little. Leave yourself about 5–10% of headroom.