LESS DISK MATH. MORE RECORDING.
Estimate file size. Keep a disk reserve. See how much recording time fits — using your numbers, not a guess about your game.
01 / YOUR INPUTS
02 / THE ESTIMATE
Enter a sample or bitrate, your session length, and a disk reserve. Then calculate.
Inputs changed. Calculate again to update these results.
Session budget
—This sample is shorter than one minute. A longer, representative recording gives a more useful average.
An estimate, not disk monitoring. It does not prevent a full disk or change recorder settings. Time is rounded down to whole minutes.
A PLAN, NOT A PROMISE
Open a finished recording's file properties and check its playback duration. File size divided by duration gives an observed average that includes its audio and container. Use the same game and settings for a useful comparison.
The reserve stays outside your recording budget. The planning buffer increases the estimated recording rate, so the reported time to reserve is more conservative. The example's 25% is a starting assumption, not a validated safety margin.
CQP, CRF, ICQ and VBR can produce different sizes with different content. A sample average is not a maximum. Check free space again, leave room for other apps, and use a representative sample rather than an idle menu screen.
Resolution, frame rate, scene complexity and encoder settings affect how much data is needed. There is no universal CQP-to-file-size conversion. This tool uses your observed file size or an entered bitrate rather than inventing one. See OBS's recording settings guide.
1 GB is 1,000,000,000 bytes. 1 GiB is 1,073,741,824 bytes. Windows frequently shows a binary count with a “GB” label. For an exact size from Properties, divide its bytes by 1,073,741,824 and select GiB, or by 1,000,000,000 and select GB. Don't mix the two.
Add video bits/second and all audio bits/second, divide by 8, and multiply by the recording's duration in seconds. For example, 8 Mbps of video with no audio for one hour is 3.6 GB before container overhead or a planning buffer. Audio tracks each contribute their own rate. See OBS's bitrate calculation example.
No. The arithmetic works for any recorder when you know the file size and duration, or the total audio/video rates. It does not inspect OBS, capture your screen, select a drive, or recommend a codec. Other recorders may use different rate-control behavior.
No file is read and entered numbers stay in this page. There are no ads, analytics or tracking scripts in this version. A public web host still receives ordinary page requests; external links have their own privacy practices. Copying an estimate writes only the summary you requested to your clipboard. Read the privacy disclosure.