Timelapse Calculator
Enter the number of shots, the interval between them and the playback frame rate to get the shooting time and the length of the finished clip. You can also work back from a clip length to the number of shots.
Formulas
- Clip length (seconds) = number of shots ÷ playback frame rate (fps)
- Shooting time (seconds) = (number of shots − 1) × interval (seconds)
- Time compression = shooting time ÷ clip length (how many times faster the action plays)
- Shots needed for a clip length = clip length × playback frame rate, rounded up to a whole number
The shooting time is the time from the first shot to the last shot. For n shots there are n − 1 intervals, so it is (shots − 1) × interval. Counting "shots × interval" would add one extra interval after the last shot. If you need the time from starting to stopping the camera, add that interval yourself.
The calculation uses exact fractions, so there is no floating-point error, and rounding happens only once when the result is shown. The number of shots needed is found from the values you entered and the exact frame rate (23.976 fps is 24000/1001), not from a clip length that was rounded for display, and it is rounded up only once at the end.
When there is only one shot
The shooting time is 0 seconds (there are no intervals). The clip length is 1 ÷ the playback frame rate (one frame). Because the shooting time is 0, the time compression is shown as "not available".
Examples
- 300 shots, 5 second interval, 24 fps: clip length 12.5 seconds, shooting time 1,495 seconds (24 min 55 s), time compression about 119.6×.
- 100 shots, 5 second interval, 24 fps: clip length about 4.166667 seconds, shooting time 495 seconds (8 min 15 s).
- Clip of 10 seconds, 2 second interval, 24 fps: 240 shots, shooting time 478 seconds (7 min 58 s).
- Clip of 10.01 seconds at 24 fps: 10.01 × 24 = 240.24, so 241 shots are needed (rounded up).
- A single shot: shooting time 0 seconds, clip length 1/24 second.
The playback frame rate
The list has 8 frame rates: 23.976, 24, 25, 29.97, 30, 50, 59.94 and 60 fps. 23.976, 29.97 and 59.94 are calculated as exact fractions (24000/1001 and so on). With "Other" you can enter a decimal or a fraction greater than 0 and at most 1,000. A decimal such as 23.976 typed in "Other" is used exactly as typed, so it differs by about one part in a million from the 23.976 fps in the list (24000/1001).
Notes
- The interval can be a decimal or a fraction, in seconds or minutes. The number of shots can be 1 to 9,999,999.
- The clip length is the time the shots take when played straight through. Slow motion or freeze frames added in editing, and export settings, are not considered.
- To convert frames to timecode, use the Timecode Calculator. To relate shutter speed and shutter angle, see the Shutter Angle Calculator.
Frequently asked questions
Why is the shooting time (shots − 1) × interval?
Because it counts the time from the first shot, taken at time 0, to the last shot. Taking n shots leaves n − 1 intervals between them.
How long is a clip of 300 shots at 24 fps?
12.5 seconds (300 ÷ 24).
How many shots do I need for a 10 second clip?
240 at 24 fps. If the result is not a whole number, it is rounded up so the clip is not shorter than you asked for.
Why is there no time compression for one shot?
The shooting time is 0 seconds, so the ratio (shooting time ÷ clip length) has no meaning.