File Size Video Calculator
Video File Size Calculator works out Average bitrate and File size from File size, Video bitrate and Audio bitrate. The default figures on this page give average bitrate of 8 Mbit/s; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
2 steps
- Bitrate = 1 MB x 8 / 1 s = 8 Mbit/s
- That is 0.001 GB decimal, or 0.0009 GiB as an operating system reports it.
Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
2 sources
What the Video File Size Calculator calculates
Relates video bitrate, duration and file size, solving for whichever is unknown, and reports the storage a recording consumes.
How to use this Video File Size Calculator
Enter File size, Video bitrate, Audio bitrate and Duration. Average bitrate updates as you type. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Average bitrate, File size and Duration.
The method follows Bitrate, duration and file size relation: size = bitrate x duration, converting bits to bytes by a factor of 8 and IEC 80000-13, quantities and units for information science and technology.
What you can compare
Change one input at a time to see how it affects Average bitrate, File size and Duration. The inputs you can vary are File size, Video bitrate, Audio bitrate, Duration and Duration in minutes.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
See something wrong? Report a problem with this calculator
Frequently asked questions
How many MB is a 30 minute video?
On the figures this page opens with — file size 1 MB and duration 1 s — the average bitrate is 8 Mbit/s. No single number fits everyone: change any figure above and the answer updates as you type, with each step of the arithmetic beside it.
How many MB is a 7 minute video?
It needs File size, Video bitrate, Audio bitrate, Duration and Duration in minutes. Nothing else is required, and the figures stay in your browser.
How many GB is a 2 hour 1080p video?
The result gives Average bitrate, File size, Duration, Total bitrate including audio and Solved for, each labelled with its unit so the figure can be read on its own.
How many GB is a 20 minute video?
The page opens with worked default figures: average bitrate of 8 Mbit/s. Replace them with your own and every figure updates as you type.
What information do I need for the Video File Size Calculator?
You need File size, Video bitrate, Audio bitrate, Duration and Duration in minutes. The page opens with default figures that give average bitrate of 8 Mbit/s, so you can see the scale before entering your own.
What does this Video File Size Calculator show?
It shows Average bitrate, File size, Duration, Total bitrate including audio and Solved for, with the working and any warnings for your entries.