Getting started
Choose a mode. Minutes and seconds add together: enter1 and30 for1 minute30 seconds. For size, supply video bitrate and its unit; for a size budget, supply the target file size. Add audio tracks together, or enter0 for silent video. Extra allowance is your assumption, not a measured average; default0% adds no overhead. Copy the result as a reference for an encoder’s average bitrate setting.
Ten minutes at2 Mbps video plus128 kbps audio with0% allowance estimates159.6 MB. For10 minutes and100 MB with128 kbps audio, the proposed video bitrate is1205 kbps.
Rules and limits
B = (video kbps + audio kbps) × 1000 × seconds ÷ 8 × (1 + reserve % ÷ 100)
This is an ABR/CBR budget model. Target mode rounds video bitrate down to whole kbps. Constant quality, VBR, container headers, subtitles, metadata and additional tracks can change actual size. This does not guarantee quality or an upload limit. MB=1,000,000 B; MiB=1,048,576 B. Editing hides the old result; reset affects this page only.