Video File Size Calculator
Calculate video file size from bitrate, duration and audio track.
About Video File Size Calculator
File size is bitrate multiplied by duration, independent of resolution except through the bitrate chosen. Newer codecs reduce size at equal quality but cost far more encoding time. Recording at a high bitrate is usually the right choice for editing, since compression can be applied at export but detail cannot be recovered.
Formula
Video File Size
Size = (video bitrate + audio bitrate) × duration ÷ 8, converted to bytes
- bitrate
- Bits per second, so dividing by eight gives bytes
- codec efficiency
- HEVC and AV1 achieve similar quality at lower bitrate
Worked example
With the default values below, Video File Size Calculator returns File Size of 3.8322. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Video bitrateminimum 0.01 Mbps
- 12 Mbps
- Audio bitrateminimum 0 kbps
- 192 kbps
- Durationminimum 0 min
- 45 min
- Saving from a newer codecaccepts 0–70 %
- 0 %
Results
- File Size
- 3.8322 GB
- File Size
- 3,924.18 MB
- Video Track Size
- 3.7719 GB
- Audio Track Size
- 61.80 MB
- Size per Hour
- 5.1096 GB
Step by step
- 1Values used
- 2Video File Size
- 3File Size= 3.8322 GB
- 4File Size= 3,924.18 MB
- 5Video Track Size= 3.7719 GB
- 6Audio Track Size= 61.80 MB
- 7Size per Hour= 5.1096 GB
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Video File Size calculated?
Size = (video bitrate + audio bitrate) × duration ÷ 8, converted to bytes File size is bitrate multiplied by duration, independent of resolution except through the bitrate chosen. Newer codecs reduce size at equal quality but cost far more encoding time.
Why does Video File Size matter?
Recording at a high bitrate is usually the right choice for editing, since compression can be applied at export but detail cannot be recovered.
What values do I need to enter?
This calculator takes 4 inputs: Video bitrate, Audio bitrate, Duration, Saving from a newer codec. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.