Timelapse Interval Calculator
Enter how long you'll shoot, the video length you want, and your frame rate to get the shutter interval and total shot count.
Shutter interval
The math behind a timelapse
A timelapse compresses a long real-world event into a short clip by capturing far fewer frames than a normal video would. The finished clip needs one frame for every frame of playback, so multiplying your target video length by the frame rate gives the exact number of stills required. Dividing your total shoot time by that number gives the interval — how often the shutter needs to fire.
A tripod is essential here: even a slight shift between frames, from wind or an unstable base, shows up as a visible jump once hundreds of stills are played back in quick succession. A sturdy, well-loaded tripod is what makes the smoothness of a good timelapse possible in the first place.
Frequently Asked Questions
How is the interval actually calculated?
A timelapse video needs one frame for every frame of the finished clip, so the total number of shots equals your target video length in seconds multiplied by the frame rate. Dividing your total shoot duration by that shot count gives the interval — the gap between one shutter press and the next.
What interval should I use for clouds, traffic, or stars?
It depends how fast the subject moves across the frame. Fast-moving clouds or city traffic often look smooth around a 2-5 second interval, a setting sun or slow clouds suit 5-10 seconds, and star trails or very slow subjects like construction or plant growth can stretch to 20-60 seconds or more. This calculator gives you the interval that fits your specific shoot duration and target clip length — pick your desired duration and length based on how fast the subject is moving.
Do I need special gear to shoot at a fixed interval?
Most cameras need an intervalometer — built into many mirrorless bodies, or added as an external remote — to trigger the shutter automatically at a set interval over a long shoot. Firing the shutter manually for hundreds of frames is impractical for anything beyond a very short timelapse.
Why might my finished clip run a little short?
The tool rounds the shot count to a whole number of frames, and in practice a shoot might end slightly early or a frame might be dropped, both of which can leave the final clip a touch shorter than planned. Shooting a small buffer of extra frames beyond the calculated total is common practice to allow trimming in the edit.
Educational tool only. Results assume every frame is captured on schedule — battery life, storage space, and mechanical shutter limits aren't modelled, so check those separately for a long shoot.