Time-Lapse Calculator — Frames, Duration and Speed Factor
Planning a time-lapse? Enter how long the real event lasts, how often you capture a frame, and the playback frame rate. Get the total frame count, final video length, and the speed-up factor — how many times faster than real life your video will appear.
minutes
seconds
fps
Length of the final time-lapse video at the chosen playback FPS
- 1
Real duration in seconds
60 × 60 = 3,600 - 2
Frames captured
⌊3,600 ÷ 5⌋ = 720 - 3
Video duration
720 ÷ 24 = 30
How does this calculator work?
Divide real duration (seconds) by the capture interval to get frame count. Divide frame count by playback FPS for video length. The speed-up factor equals real duration divided by video duration. A 1-hour event captured every 5 s and played at 24 fps gives 720 frames and a 30-second video at 120× speed.
Formula
How this is calculated
A time-lapse works by capturing frames at a fixed interval (e.g. every 5 seconds) and then playing them back at a much higher rate (e.g. 24 frames per second). The total number of frames is simply the real-world duration in seconds divided by the capture interval. Playing those frames at the chosen FPS gives the final video length.
The speed-up factor — how many times faster than real life the video appears — equals the real duration divided by the video duration, which is the same as FPS ÷ (1 / interval) = FPS × interval. A 5-second interval at 24 fps produces a 120× speed-up: one minute of real time compresses to 0.5 seconds of video.
Storage estimation assumes roughly 4 KB per JPEG frame at moderate resolution, which is a very rough figure — actual file sizes depend heavily on camera, resolution, compression settings and scene complexity. RAW files are typically 10–40× larger per frame.
Frequently asked questions
It depends on how slowly the subject moves. Clouds: 5–10 s. Sunsets/sunrises: 2–5 s. Plant growth over days: 1–10 min. Construction over weeks: 30 min to several hours. A good rule of thumb: choose an interval that gives at least 200–300 frames for a smooth clip.
Decide on your frame rate (e.g. 24 fps) and compute the frames needed: 30 s × 24 fps = 720 frames. Then choose the interval to cover the event duration: if the event lasts 1 hour (3600 s), interval = 3600 / 720 = 5 seconds.
Yes. For a fixed playback FPS, a longer capture interval means fewer frames per real-world second, so the video plays faster relative to reality. Doubling the interval doubles the speed-up factor.
Also known as
TG we-Calculate Editorial Team. (2026). Time-Lapse Calculator — Frames, Duration and Speed Factor [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/time-lapse-calculator
TG we-Calculate Editorial Team. "Time-Lapse Calculator — Frames, Duration and Speed Factor." TG we-Calculate. 2026. https://we-calculate.com/calculator/time-lapse-calculator.
TG we-Calculate Editorial Team, "Time-Lapse Calculator — Frames, Duration and Speed Factor," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/time-lapse-calculator
@misc{wecalculate_time_lapse_calculator, title = {Time-Lapse Calculator — Frames, Duration and Speed Factor}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/time-lapse-calculator}}, year = {2026}, note = {TG we-Calculate} }
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