# How long will my time lapse be?

Works out how many photos a time-lapse takes and how long the clip will be from the event length, shooting interval and frame rate, or the interval to use for a clip length you want.

- Page: https://www.acalculator.org/everyday-life/time-lapse-calculator
- JSON spec: https://www.acalculator.org/everyday-life/time-lapse-calculator.json
- Version: 9aa3542db8c7

## Default answer

Example with the default inputs (Work out Clip length, Event length 2 h, Interval 5 s, Frame rate (fps) 30): A 48 s clip: 1,440 photos played at 30 fps.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| find | Work out | The clip length from an interval, or the interval for a clip length. |
| ev | Event length | How long you will shoot for. |
| int | Interval | The time between two photos. |
| clip | Clip length | How long you want the finished video to be. |
| fps | Frame rate (fps) | Frames per second of the finished video; 24, 25, 30 and 60 are common. |
| mb | Photo size (MB) | Optional: the size of one photo file in megabytes, to estimate the storage. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| result | Answer | The clip length, or the interval to shoot at. |
| photos | Photos | Event length ÷ interval, in whole photos. |
| clipLength | Clip length | Photos ÷ frame rate. |
| intervalLength | Interval | The time between two photos. |
| speed | Speed-up | Interval × frame rate: how many times faster than real time the clip plays. |
| storage | Storage | Photos × photo size, in gigabytes (1 GB = 1,000 MB). |

## Method

Photos = ⌊event length ÷ interval⌋; clip length = photos ÷ fps. For a clip length: photos = ⌈clip length × fps⌉; interval = event length ÷ photos.

## Assumptions

- Photos are counted in whole intervals over the event; a part of an interval at the end takes no photo.
- Every photo becomes one frame of the video.
- 1 GB = 1,000 MB, as storage cards are sold.

## Worked examples

1. find = clip, ev = 86,400, int = 30, fps = 24 gives photos = 2,880, clipLength = 120, result = A 2 min 0 s clip, speed = 720. Source: Time-lapse photography, Wikipedia (one frame every 30 seconds for 24 hours gives 2,880 frames, about 2 minutes at 24 frames per second), https://en.wikipedia.org/wiki/Time-lapse_photography (retrieved 2026-10-03).
2. find = interval, ev = 14,400, clip = 45, fps = 24 gives photos = 1,080, intervalLength = 13.333333, result = Shoot every 13.33 s. Source: Time-lapse photography, Wikipedia (one frame every 30 seconds for 24 hours gives 2,880 frames, about 2 minutes at 24 frames per second), https://en.wikipedia.org/wiki/Time-lapse_photography (retrieved 2026-10-03).
3. find = clip, ev = 7,200, int = 7, fps = 30, mb = 25 gives photos = 1,028, clipLength = 34.266667, storage = 25.7. Source: Time-lapse photography, Wikipedia (one frame every 30 seconds for 24 hours gives 2,880 frames, about 2 minutes at 24 frames per second), https://en.wikipedia.org/wiki/Time-lapse_photography (retrieved 2026-10-03).

## FAQ

### How do I calculate a time-lapse?

Divide the event length by the interval to get the number of photos, then divide the photos by the frame rate to get the clip length. 2 hours (7,200 s) at one photo every 5 s is 1,440 photos; at 30 fps that is a 48 s clip.

### What interval should I use for a time-lapse?

Multiply the clip length you want by the frame rate to get the photos you need, then divide the event length by that number. For a 45 s clip at 24 fps from a 4-hour event: 45 × 24 = 1,080 photos, and 14,400 s ÷ 1,080 = 13.3 s between photos.

### What intervals suit common subjects?

Fast clouds and traffic look smooth at 1 s to 3 s, slow clouds and sunsets at 3 s to 10 s, stars at 15 s to 30 s, and plants or building work at minutes to hours. Shorter intervals give smoother but slower motion.

### How much faster than real time does a time-lapse play?

The interval times the frame rate. At one photo every 5 s played at 30 fps, every second of video shows 150 s of real time.

### Which frame rate should I pick?

24 fps gives a film look, 25 fps is used for PAL video, and 30 fps for most online video. A higher frame rate needs more photos for the same clip length.

### How much storage will a time-lapse need?

Multiply the number of photos by the size of one photo. 1,028 RAW photos of 25 MB each need about 25.7 GB.

## Sources

- Time-lapse photography, Wikipedia (one frame every 30 seconds over 24 hours gives 2,880 frames, about 2 minutes at 24 frames per second). https://en.wikipedia.org/wiki/Time-lapse_photography (retrieved 2026-10-03)