Bitrate Calculator
Estimate a video or audio file's size from its bitrate and duration, or the bitrate for a target size.
Bitrate, duration and file size
A media file's size comes down to its bitrate — how much data per second — times its duration. This calculates any of the three from the other two, so you can estimate how big a recording will be, work out the bitrate to hit a target size, or check whether a file will fit a limit before you export it.
Enter two of bitrate, duration and size, and get the third.
The quality-versus-size trade-off
Bitrate is the dial that trades quality against size: a higher bitrate carries more detail and looks or sounds better, but makes a bigger file, while a lower one saves space at the cost of quality. That is the whole balancing act of exporting media. If you have a size limit — a platform's cap, a disc, an email — this tells you the bitrate to target to fit it, and conversely how large a given quality will run. Understanding the relationship turns exporting from trial-and-error into a calculated choice.
Common questions
How does bitrate affect file size and quality?
Higher bitrate means more data per second — better quality but a larger file. It is the main trade-off when exporting media.
Can it tell me the bitrate to hit a size limit?
Yes — enter the target size and duration and it gives the bitrate to aim for so the file fits.
Is anything uploaded?
No. The calculation happens in your browser.