FreeToolStation

Video Bitrate Calculator

Bitrate, duration and file size, any one from the others.

Tech Calculators Free, no sign-up Runs in your browser

For the first option.

For the second option.

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Result
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Total bitrate
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File size
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Per minute
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Typical quality
PresetVideo bitrateFile size
Bitrate is quoted in megabits per second and file size in megabytes, a factor of eight apart. Audio adds up too: 192 kbps across 45 minutes is 65 MB on its own, which is why it is a separate input rather than an afterthought.

About the Video Bitrate Calculator

Video Bitrate Calculator works in both directions. Give it a bitrate and a duration and it returns the file size; give it a target size instead and it returns the bitrate that will fit. Audio is a separate input in both cases, because at 192 kbps it contributes over a megabyte a minute and ignoring it is how an export overruns its target.

The arithmetic is simply bitrate multiplied by time, with the factor of eight between bits and bytes applied once. Eight megabits per second for forty-five minutes is 21,600 megabits, which is 2,700 megabytes of video before the audio track is added. The reason to use a calculator is not the difficulty but the unit mismatch, which is responsible for almost every wrong answer in this area.

The preset table gives the bitrates platforms actually recommend for each resolution and frame rate, so you can see what your target size buys. If the bitrate needed to fit a size falls below the preset for your resolution, the honest options are a lower resolution, a more efficient codec, or a larger file -- compressing harder at the same resolution will show.

The page shows its working, not just its answer. Where there is a formula it is printed with your own numbers substituted in, so you can check the result rather than take it on trust -- which is the difference between a calculator you can use for something that matters and one you cannot.

Everything runs inside your browser. What you type is never uploaded, never logged and never stored, and the calculator keeps working if your connection drops after the page has loaded.

Looking for something this does not cover? FreeToolsZone.org is more free browser-based tools, organised by job, and it is worth a look if video bitrate calculator is only part of what you are working on.

How to use the Video Bitrate Calculator

  1. Choose work out and target unitThe fields below change to match what you pick, so only the figures that matter to your case are asked for.
  2. Enter duration (minutes), video bitrate (mbps) and audio bitrate (kbps)Decimals are fine, and thousands separators are accepted and ignored.
  3. Read the result, total bitrate and file sizeThe figures update as you type. The Calculate button is there if you would rather press something, but nothing waits for it.
  4. Copy or check the resultCopy the summary with the copy button, or open the table to check it row by row.

Features

  • Shows result, total bitrate, file size, per minute and typical quality together, so you are not running it twice
  • A results table you can read across
  • Updates as you type, with no button to press and no page reload
  • Copy the result in one click
  • Free, no sign-up, and it runs entirely in your browser

Who uses this tool

The video bitrate calculator is used by writers, developers, students, marketers and anyone else who needs the job done once without installing software. Common cases include:

  • Choosing an export bitrate to fit a size limit
  • Estimating the size of a recording before making it
  • Checking whether a bitrate is adequate for 1080p or 4K
  • Budgeting storage for a batch of video files

Frequently asked questions

What bitrate should I use for 1080p?

Around 8 Mbps at 30fps and 12 Mbps at 60fps for H.264. A modern codec like H.265 or AV1 looks the same at roughly half that.

Why is my file bigger than the calculator says?

Container overhead, variable bitrate peaks and multiple audio tracks all add a little. Expect a few per cent above the calculated figure.

Does the codec matter?

Very much for quality at a given bitrate, but not for the size arithmetic. The calculator works from bitrate, whichever codec produced it.

Should I use constant or variable bitrate?

Variable gives better quality for the same average size, but the average is what this calculation uses, so plan with the average figure.

If the video bitrate calculator is not quite what you need, these other free tools solve closely related problems, and there are 11 more in tech calculators.

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Bytes to KB, MB, GB and the KiB/MiB/GiB family.

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Time Duration Calculator

The gap between two times, or a duration added to or taken from a time.

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Checked and rebuilt on 2026-10-14. The method this calculator uses is described in the section above, and corrections go through the contact page.