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Video Frame Rate Calculator

Video & AudioMedia Utilities

The rate the camera recorded at. 23.976 and 29.97 are the NTSC rates (24000/1001 and 30000/1001).

The project or delivery rate the clip is conformed to.

Playback speed —
Effect
—
Slowdown factor (capture ÷ playback)
—
Frames recorded
—
Length on the timeline (s)
—
Capture frame interval (ms)
—
Playback frame interval (ms)
—

Playback speed equals the timeline frame rate divided by the capture frame rate. Footage shot at 120 fps and placed on a 24 fps timeline plays at 24 ÷ 120 = 20% speed, which is 5× slow motion: 10 seconds of action holds 1,200 frames and runs 50 seconds on screen.

About this tool

Editors, camera operators and anyone planning a slow-motion or time-lapse shot need to know what happens when a clip's recorded frame rate differs from the project rate. Enter the rate the camera captured at, the rate of the timeline or delivery file, and how long you recorded. The calculator returns the playback speed as a percentage, the slowdown factor, the number of frames captured, how long the clip lasts once every frame is played back, and the time each frame stays on screen at both rates. It assumes every captured frame is kept and none are blended or dropped; if your editor retimes the clip to real speed instead of conforming it, frames are skipped or repeated and the timeline length stays the same as the recorded length.

How to use it

  1. Enter the capture rate

    Type the frame rate the camera recorded at, such as 60, 120 or 240 fps, or 1 for a one-frame-per-second time-lapse.

  2. Enter the playback rate

    Type the frame rate of your timeline or export, commonly 23.976, 24, 25 or 29.97 fps.

  3. Enter the recorded length

    Give the real-world duration of the shot, measured as a number of seconds.

  4. Read the results

    Speed, slowdown factor, frame count, timeline length and per-frame intervals update as you type, with the working shown below.

Examples

23.976 fps shot and played at 23.976 fps

Capture frame rate
23.976
Playback (timeline) frame rate
23.976
Recorded length
10

Result Playback speed: 100%
Effect: Real time
Slowdown factor (capture ÷ playback): 1
Frames recorded: 240
Length on the timeline (s): 10
Capture frame interval (ms): 41.708
Playback frame interval (ms): 41.708

  1. Frames recorded = 23.976 fps × 10 s = 239.76
  2. Output length = 239.76 ÷ 23.976 fps = 10 s
  3. Playback speed = 23.976 ÷ 23.976 × 100 = 100%
  4. Frame interval = 1000 ÷ 23.976 = 41.708 ms (capture), 1000 ÷ 23.976 = 41.708 ms (playback)

Matching rates play at 100% speed; each frame is on screen for about 41.7 ms.

120 fps on a 24 fps timeline

Capture frame rate
120
Playback (timeline) frame rate
24
Recorded length
10

Result Playback speed: 20%
Effect: Slow motion
Slowdown factor (capture ÷ playback): 5
Frames recorded: 1,200
Length on the timeline (s): 50
Capture frame interval (ms): 8.333
Playback frame interval (ms): 41.667

  1. Frames recorded = 120 fps × 10 s = 1200
  2. Output length = 1200 ÷ 24 fps = 50 s
  3. Playback speed = 24 ÷ 120 × 100 = 20%
  4. Frame interval = 1000 ÷ 120 = 8.333 ms (capture), 1000 ÷ 24 = 41.667 ms (playback)

1,200 frames shown 24 per second last 50 s, so 10 s of action becomes 5× slow motion at 20% speed.

One frame a second for an hour, played at 30 fps

Capture frame rate
1
Playback (timeline) frame rate
30
Recorded length
3600

Result Playback speed: 3,000%
Effect: Time-lapse / fast motion
Slowdown factor (capture ÷ playback): 0.033
Frames recorded: 3,600
Length on the timeline (s): 120
Capture frame interval (ms): 1,000
Playback frame interval (ms): 33.333

  1. Frames recorded = 1 fps × 3600 s = 3600
  2. Output length = 3600 ÷ 30 fps = 120 s
  3. Playback speed = 30 ÷ 1 × 100 = 3000%
  4. Frame interval = 1000 ÷ 1 = 1000 ms (capture), 1000 ÷ 30 = 33.333 ms (playback)

3,600 frames at 30 fps run for 2 minutes, 30 times faster than real time.

How it is calculated

speed % = (playback fps ÷ capture fps) × 100; frames = capture fps × t; output length = frames ÷ playback fps

capture fps
Frames per second recorded by the camera
playback fps
Frames per second of the timeline or delivery file
t
Recorded duration, measured as a number of seconds

A conformed clip shows every recorded frame once, at the timeline rate. The frame count is fixed by capture, so the on-screen length scales by capture fps ÷ playback fps. A factor above 1 slows motion down; below 1 it speeds it up. The frame interval, 1000 ÷ fps milliseconds, is how long each frame is displayed. NTSC rates such as 23.976 and 29.97 are exactly 24000/1001 and 30000/1001, so enter them to three decimals for close results.

When not to use it

  • It does not estimate file size or bitrate for a given frame rate.
  • It does not model optical-flow retiming, which invents frames between real ones.
  • It does not convert drop-frame timecode labels to frame counts.

Common mistakes

  • Entering 30 when the camera actually recorded 29.97 fps, which drifts by about 3.6 seconds per hour.
  • Expecting slow motion from high-frame-rate footage placed on a timeline set to the same high rate.
  • Using the timeline length as the recorded length when working backwards from an edit.

Frequently asked questions

How much slow motion do I get from 60 fps on a 24 fps timeline?

The slowdown factor is 60 ÷ 24 = 2.5, so the clip plays at 40% speed. A 4-second move becomes 10 seconds on screen.

Why is 23.976 used instead of 24?

When colour was added to NTSC television, the frame rate was lowered by a factor of 1000/1001 to avoid interference with the colour subcarrier. Film-derived video at 24 fps therefore runs at 24000/1001, about 23.976 fps, and 30 fps becomes 29.97.

What happens when PAL footage at 25 fps is conformed to 24 fps?

Every frame is kept, so the clip plays at 96% speed and runs 4.17% longer: a 60-second shot becomes 62.5 seconds. Audio played at the same rate drops in pitch by about 0.7 semitones unless it is pitch-corrected.

How do I plan a time-lapse length with this?

Treat the interval as a frame rate. One shot every 2 seconds is 0.5 fps. An hour of shooting at 0.5 fps gives 1,800 frames, which last 60 seconds at 30 fps playback.

What is the frame interval?

It is how long one frame stays on screen: 1000 ÷ fps milliseconds. At 24 fps that is 41.667 ms, at 60 fps 16.667 ms. It also sets the upper limit for shutter time, because a shutter cannot stay open longer than one frame.

Does a higher capture rate always look smoother in slow motion?

Only when it is conformed to a lower timeline rate. If you shoot 120 fps and export at 120 fps, playback is real time and motion looks the same speed, just with more frames per second on displays that can show them.

Cite this tool

Using this tool in an assignment, article or report? Copy a citation, or a link for your website.

APA

Tools Directory Editorial Team. (2026, October 18). Video Frame Rate Calculator. Tools Directory. Retrieved October 26, 2026, from https://tools.milunir.com/video-audio/media-utilities/video-frame-rate-calculator/

MLA

Tools Directory Editorial Team. “Video Frame Rate Calculator.” Tools Directory, 18 Oct. 2026, https://tools.milunir.com/video-audio/media-utilities/video-frame-rate-calculator/. Accessed 26 Oct. 2026.

Chicago

Tools Directory Editorial Team. “Video Frame Rate Calculator.” Tools Directory. Last modified October 18, 2026. Accessed October 26, 2026. https://tools.milunir.com/video-audio/media-utilities/video-frame-rate-calculator/.

Link<a href="https://tools.milunir.com/video-audio/media-utilities/video-frame-rate-calculator/">Video Frame Rate Calculator – Tools Directory</a>