Bitrate Calculator

Video and audio bitrate: bits per second of a stream

Bitrate tells you how much data each second of a media stream carries, and you get it from bitrate = file_size · 8 / duration. A 100 MB clip running 60 s comes out to (100 · 8) / 60 ≈ 13.3 Mbps. On the video side, H.264 usually lands around ~8 Mbps for 1080p and 25–40 Mbps for 4K on YouTube. H.265 (HEVC) hits the same quality on roughly half the bitrate, and AV1 shaves off another ~30% on top of HEVC. With audio, MP3 runs at 128/192/320 kbps, AAC matches that quality at lower rates, Opus is very efficient for voice, and FLAC is lossless at ~1000 kbps. Each platform publishes its own targets: YouTube wants 8–12 Mbps for 1080p60 and 35–45 Mbps for 4K60, while Twitch livestreams cap out at 6 Mbps. As for encoding modes, you choose between CBR (constant), VBR (variable) and CRF (constant quality target).

Applications: production, streaming and OTT

Editors working in Premiere or DaVinci set bitrate to trade off quality against disk space. Livestreamers tune CBR so it fits the upload bandwidth they have on Twitch and YouTube Live. Podcasters tend to aim for 96–128 kbps AAC to keep episode files small. And OTT services like Netflix and Disney+ ship several bitrate ladders at once so the player can adapt to whatever connection the viewer has, which is what ABR (adaptive bitrate streaming) is all about.

FAQ

Higher bitrate always means better quality? Only up to a point. Once you pass the codec's efficiency ceiling, the extra bits buy you less and less, and the encoder and resolution end up mattering more.

CBR or VBR? Go with CBR for live streaming, where predictable bandwidth is what counts. For on-demand files, VBR or CRF gives you more quality per MB.

How do kbps and Mbps relate to MB/s? Just divide by 8, so 8 Mbps ≈ 1 MB/s. A 90-minute movie at 8 Mbps works out to about 8 · 5400 / 8 ≈ 5.4 GB.