Frame-rate calculator

What this tool does

frame_count ≈ duration * fps, rounded to the nearest frame. That rounding is stated. Drop-frame timecode is not implemented.

How to use it

1. Enter any two of duration, fps, and frame count.
2. Read the third.
3. Do not mix 24.000 and 23.976 in one calculation unless you mean to.

Privacy

This tool processes files and text locally in your browser. Your content is not uploaded or stored by this site.

ConvertPass does not include your input in analytics, URLs, or error reports. Encoding: N/A. Limit: N/A (1.0 KB).

Limitations

• Drop-frame SMPTE math is not included.
• Variable frame rate files cannot be described by one fps.

Example

duration 10s at 24 fps

240 frames

Troubleshooting

Off by one frame

Rounding and inclusive/exclusive end frames differ between NLEs. Use this as an estimate, then confirm on a timeline.

FAQ

Is 29.97 the same as 30?

No. Broadcast NTSC rates are not integers. If your project is 29.97, enter 29.97.

Can I read fps from a file?

Browsers rarely expose an accurate fps. Type the rate from your editor instead of hoping the video element knows.

What about 120 fps slow motion?

Enter 120. Playback rate is a different number.

Does this change the file?

No.