BYTETOOLS

Video Bitrate Calculator

Work out the bitrate that fits a target file size, or the file size a bitrate produces. Includes audio budget, container overhead and recommended bitrates by resolution.

Video length

Result

685 kbps
Total bitrate
557 kbps
Video bitrate
25.0 MB
Target size
4.90 MB
Per minute

At 685 kbps an hour of this video is about 294.0 MB.

-c:v libx264 -b:v 557k -maxrate 557k -bufsize 1114k -c:a aac -b:a 128k

Recommended bitrates by resolution

Resolution24–30 fps48–60 fpsSize per minute
2160p (4K)35–45 Mbps53–68 Mbps321.9 MB
1440p (2K)16 Mbps24 Mbps114.4 MB
1080p8 Mbps12 Mbps57.2 MB
720p5 Mbps7.5 Mbps35.8 MB
480p2.5 Mbps4 Mbps17.9 MB
360p1 Mbps1.5 Mbps7.15 MB

The H.264 column reproduces YouTube's published recommended upload bitrates for SDR video. They are upload targets, deliberately generous — a well-encoded 1080p clip for a website often looks fine at half these numbers.

What is the Video Bitrate Calculator?

The ByteTools Video Bitrate Calculator solves the encoding triangle in both directions. Give it a target file size and a video length and it returns the total bitrate you can spend, minus the audio budget, leaving the video bitrate to pass to your encoder.

  • Works in both directions: size to bitrate, or bitrate to size
  • Subtracts the audio budget to give a usable video bitrate
  • Explicit binary or decimal megabyte convention
  • Container overhead allowance so the result actually fits
  • Presets for Discord, email, WhatsApp and DVD limits
  • Copyable ffmpeg flags and a YouTube bitrate reference table

How to use the Video Bitrate Calculator

  1. 1

    Choose whether you are working out a bitrate from a size, or a size from a bitrate.

  2. 2

    Enter the video length in hours, minutes and seconds.

  3. 3

    Enter your target file size (or total bitrate), and pick the audio bitrate.

  4. 4

    Adjust the container overhead and megabyte convention if you need to.

  5. 5

    Read the total and video bitrate, then copy the ffmpeg flags if you want them.

About the Video Bitrate Calculator

The ByteTools Video Bitrate Calculator solves the encoding triangle in both directions. Give it a target file size and a video length and it returns the total bitrate you can spend, minus the audio budget, leaving the video bitrate to pass to your encoder. Switch modes and it does the reverse: enter a bitrate and see how big the file will be.

It is honest about the details that trip people up. You choose whether a megabyte means 1,048,576 bytes (what Discord, Windows and most upload limits mean) or 1,000,000, and there is a container overhead setting because muxing headers and indexes really do take a couple of percent. Preset buttons cover common limits, and the finished settings are shown as a copyable line of ffmpeg flags.

A reference table lists YouTube's published recommended upload bitrates by resolution, with a codec selector that scales them for HEVC, VP9 and AV1. Those scaled figures are rules of thumb, not published targets, and the page says so. Everything is calculated instantly in your browser — nothing is uploaded and no file is needed.

Frequently asked questions

How do I calculate video bitrate from file size?

Multiply the file size in bytes by eight to get bits, then divide by the length in seconds. This calculator does it for you and also subtracts the audio bitrate, so the number it gives you is the video bitrate to put into your encoder.

What bitrate should I use for 1080p video?

YouTube's published recommendation for 1080p SDR uploads is 8 Mbps at standard frame rates and 12 Mbps at 48–60 fps. Those are deliberately generous upload targets — a 1080p clip destined for a website often looks fine at half that.

How do I fit a video under Discord's 10 MB limit?

Click the Discord free preset, enter your clip's length and pick an audio bitrate, and the calculator shows the video bitrate that fits. If that number lands below about 300 kbps, the clip is too long for the limit and needs trimming or a smaller frame size.

Why does the calculator ask about megabytes being 1,048,576 bytes?

Because the two definitions differ by about 5%, which is enough to push a file over an upload limit. Discord, Windows and most services mean 1,048,576 bytes, while drive manufacturers mean 1,000,000, so the calculator makes you pick rather than guessing.

Is HEVC or AV1 really half the bitrate of H.264?

Roughly, for similar perceived quality, but it varies a lot with content and encoder settings. The codec selector here scales the H.264 figures by 55% for HEVC and VP9 and 45% for AV1 as a planning rule of thumb, not as a guaranteed result.

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