Frame Rate Conversion Calculator
Convert a frame count between frame rates in two ways. Keep the real time and find the new number of frames, or keep the frames and find the new length and speed.
"Keep the real time" and "keep the frame count"
The frame rate (fps) is the number of frames per second. When you change it, there are two ways to look at what stays the same and what changes.
| Keep the real time | Keep the frame count | |
|---|---|---|
| Stays the same | The length (seconds) | The number of frames |
| Changes | The number of frames | The length and the playback speed |
| The question | How many frames does the same length of video need at another frame rate? | If the same frames are played at another rate, how long is the clip and how much faster is it? |
| Example | 10 s at 24 fps (240 frames) is 250 frames at 25 fps | 60 s at 24 fps (1,440 frames) played at 25 fps is 57.6 s (about 4.17% faster) |
How it is calculated
- Keep the real time: new frames = original frames × new rate ÷ original rate (when it is not a whole number, it is rounded to a whole number by the method you choose).
- Keep the frame count: new length = frames ÷ new rate. The speed ratio = new rate ÷ original rate (above 1 means faster and shorter).
23.976, 29.97 and 59.94 fps are calculated as exact fractions (24000/1001, 30000/1001 and 60000/1001). No decimal error creeps in, and rounding happens only once, at the end.
Example: 24 fps and 25 fps
When a 24 fps film is played back at 25 fps without changing the number of frames, it runs about 4.17% faster and is about 4% shorter.
- Keep the frame count: 1,440 frames (60 s) at 24 fps played at 25 fps is 57.6 s (−2.4 s). The speed is 104.17% (25 ÷ 24).
- Keep the real time: 240 frames (10 s) at 24 fps is 250 frames at 25 fps (the length stays 10 s). The 10 extra frames have to be made by repeating or interpolating frames, which this calculator does not cover.
29.97 fps and 30 fps
29.97 fps is exactly 30000/1001 fps (about 29.97003 fps), about 0.1% slower than 30 fps. For example, 1,001 frames last about 33.4000 s at 29.97 fps and about 33.3667 s at 30 fps (playing the same frames at 30 fps is about 0.0334 s shorter, at 100.1% speed). For how timecode is counted, see the Timecode Calculator.
More examples
- Keep the real time: 240 frames at 24 fps → 300 frames at 30 fps, 250 frames at 25 fps, or 600 frames at 60 fps.
- Keep the frame count: 1,440 frames at 24 fps → 57.6 s at 25 fps (104.17% speed) or 48 s at 30 fps (125% speed).
- Keep the frame count: 1,800 frames (60 s) at 30 fps → 75 s at 24 fps (80% speed).
Things to know
- Enter the original number of frames as a whole number from 0 to 999,999,999. Commas as thousands separators are accepted.
- The frame rate is one of 23.976, 24, 25, 29.97, 30, 50, 59.94 and 60 fps. Other frame rates are not supported.
- How frames are repeated, dropped or interpolated when real video is converted (for example 2:3 pulldown) is not covered. The effect on the length and pitch of the audio is not covered either.
- To turn a timecode into a number of frames, use the Timecode Calculator.
Frequently asked questions
If I change a 24 fps video to 30 fps, does the length change?
It depends on the approach. If you keep the real time, the length stays the same and the number of frames becomes 1.25 times as many (240 frames become 300). If you keep the frame count and play it at 30 fps, the length becomes 0.8 times (10 s become 8 s) and the speed is 1.25 times.
How much faster is 25 fps than 24 fps?
Playing the same frames at 25 fps is 25 ÷ 24 = about 1.0417 times as fast, about 4.17% faster. The length is about 4% shorter.
What is the difference between 23.976 fps and 24 fps?
23.976 fps is exactly 24000/1001 fps, about 0.1% slower than 24 fps. This calculator uses that fraction exactly.