How is the time-lapse interval calculated?

First the tool finds the total frames needed: clip length in seconds × playback frame rate. Then the shooting interval equals the real-world duration divided by that frame count. For a 20-second clip at 24 fps you need 480 frames, so a two-hour event needs one frame every 15 seconds.

What frame rate should I use for a time-lapse?

24 fps gives a cinematic look and is the most common choice, while 30 fps suits broadcast and smoother motion. Higher rates like 60 fps need more frames and shorter intervals, which means more shots and more storage for the same clip length.

What interval should I use for clouds, sunsets, or stars?

Fast-moving clouds suit 2–5 second intervals, sunsets around 3–6 seconds, slow-building scenes 10–30 seconds, and star trails or night skies often 20–40 seconds. The calculator gives the exact interval for your chosen duration and clip length, which you can fine-tune from these ranges.

Why is my camera falling behind the interval?

If the chosen interval is shorter than the exposure time plus the time the camera needs to write each file to the card, the camera cannot keep up and skips frames. Lengthen the clip, extend the real duration, or shorten exposures so the interval comfortably exceeds your per-shot time.

How much storage will a time-lapse need?

Multiply the total frame count by the file size of each frame. Shooting RAW at 12 MB per frame for an 800-frame sequence needs roughly 9.4 GB. This tool estimates storage when you enter a per-frame file size, so you can confirm your card is large enough before you start.

Time-Lapse Interval & Clip Length Calculator

A time-lapse turns hours of real time into seconds of video. This calculator works out the exact interval to program into your intervalometer so your final clip lands at the length you want, at the frame rate you want.

How it works

Three values define every time-lapse:

Total frames = clip length (s) × playback frame rate (fps)

Interval = real-world duration (s) ÷ total frames

Speed-up factor = real-world duration ÷ clip length

So if you want a 20-second clip at 24 fps, you need 480 frames. Spreading those 480 frames across a two-hour (7,200-second) event gives an interval of 7,200 ÷ 480 = 15 seconds per shot, and the finished clip plays 360× faster than real life.

Worked example

You want to capture a 4-hour sunset-to-night sequence as a 30-second clip at 30 fps:

Total frames = 30 × 30 = 900
Interval = 14,400 s ÷ 900 = 16 seconds
Speed-up = 14,400 ÷ 30 = 480× faster

At 12 MB per RAW frame, that is 900 × 12 ≈ 10.5 GB of storage.

Tips and notes

Make sure the interval is longer than your exposure time plus the card write time, or the camera will skip frames and the clip will be short.
Shorter intervals give smoother motion but more frames, more storage, and more shutter actuations.
Typical starting intervals: clouds 2–5 s, sunsets 3–6 s, general scenes 10–30 s, stars 20–40 s.
All maths runs locally in your browser; nothing about your shoot is uploaded.