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Motion and shutter tool

Frame Rate Calculator: FPS, Shutter Angle & Slow Motion ToolFrame Rate

Turn a shutter angle into a shutter speed, and work out how long you have to roll for the slow motion you want.

Shutter angleSlow motionFlicker free

01 / Shutter

Angle to shutter speed

24 fps · 180°

Shutter speed

1/48s

20.83 ms per frame

The sensor sees light for 50% of every frame.

Frame rate

What the camera records at.

Shutter angle

180 degrees is the cinema default.

Shutter speed

Or dial the speed and read the angle.

An angle keeps the same motion blur at any frame rate, which is why cinema cameras show it instead of a speed.

02 / Speed

Slow motion and conform

120 fps into a 24 fps timeline

Slow motion

5.00× slower20.0% speed

One second in front of the camera fills 5.00s on the timeline.

Capture

What you set on the camera.

Timeline

What the edit runs at.

Both fields are linked, so you can plan from the shoot side or from the edit side.

03 / Rates

What each capture rate gives you

At 24 fps

Higher capture rates need more light, because the shutter has less time open per frame.

Common Frame Rates

Reference chart of standard cinema, broadcast, and high-speed frame rates with their 180-degree shutter speeds and typical applications

Frame RateRegion / StandardShutter Speed (180°)Common Use
23.976 fpsNTSC Cinema1/48sTheatrical film / streaming
24 fpsCinema1/48sTrue cinema
25 fpsPAL1/50sEuropean broadcast / web
29.97 fpsNTSC1/60sUS broadcast
30 fpsWeb1/60sYouTube / web content
48 fpsHFR Cinema1/96sHigh frame rate cinema
50 fpsPAL Slow-mo1/100s2× slow motion PAL
59.94 fpsNTSC Slow-mo1/120s2× slow motion NTSC
60 fpsGaming / Web1/120sSports / gaming
120 fpsSlow Motion1/240s4–5× slow motion
240 fpsSuper Slow-mo1/480s8–10× slow motion
1000 fpsUltra Slow-mo1/2000sPhantom / specialized

Slow Motion Reference

How different capture frame rates translate to slow motion at common playback speeds

Capture FPSPlayback 24fpsPlayback 25fpsPlayback 30fpsSpeed %
48 fps2× slower1.92× slower1.6× slower50%
50 fps2.08× slower2× slower1.67× slower48%
60 fps2.5× slower2.4× slower2× slower40%
96 fps4× slower3.84× slower3.2× slower25%
120 fps5× slower4.8× slower4× slower20%
180 fps7.5× slower7.2× slower6× slower13.3%
240 fps10× slower9.6× slower8× slower10%
480 fps20× slower19.2× slower16× slower5%
1000 fps41.7× slower40× slower33.3× slower2.4%

How Shutter Angle Works

The shutter angle system originates from rotary disc shutters in film cameras. It describes exposure time as a fraction of the frame period, ensuring consistent motion blur across different frame rates.

The 180° Standard

A 180-degree shutter angle exposes the sensor for exactly half the frame duration. This produces the natural motion blur audiences associate with cinematic footage. It's been the default in filmmaking since the early days of cinema.

24fps → 1/48s

25fps → 1/50s

30fps → 1/60s

Always 2× frame rate

Creative Shutter Angles

Deviating from 180° creates distinct visual styles. Narrow angles (45°–90°) produce sharp, staccato motion with minimal blur. Wide angles (270°–360°) create dreamy, smeared movement with heavy motion blur.

45° → sharp, jittery

90° → staccato action

270° → dreamy blur

Match the mood of your scene

Anti-Flicker Shutter Angles

Artificial lighting flickers at the mains frequency (50Hz or 60Hz). Your shutter speed must be a multiple of that frequency to avoid banding. At 24fps, 180° gives 1/48s which doesn't divide evenly into 50Hz, so use 172.8° instead to get exactly 1/50s. At 25fps, 180° already gives 1/50s, so no adjustment needed.

24fps + 50Hz → 172.8° (= 1/50s)

25fps + 50Hz → 180° (= 1/50s)

30fps + 60Hz → 180° (= 1/60s)

24fps + 60Hz → 144° (= 1/60s)

Shutter speed must be multiple of 1/Hz

The General Formula

Convert any shutter angle to a shutter speed using this formula:

Shutter Speed = 1 / (FPS × 360 / Angle)

FPS = frame rate, Angle = shutter angle in degrees

Example: 24fps, 180° → 1 / (24 × 2) = 1/48s

Simplified for 180°

At the standard 180-degree shutter angle, the formula simplifies to:

Shutter Speed = 1 / (2 × FPS)

This is why the 180° rule is also called the "double your frame rate" rule

60fps → 1/120s · 120fps → 1/240s

Frequently Asked Questions

Common questions about frame rates, shutter angle, and slow motion

24fps (actually 23.976fps for NTSC) is the standard cinema frame rate used in theatrical films worldwide. 25fps is the PAL standard used in European broadcast television. The difference stems from historical electrical frequency standards: 60Hz in North America led to 29.97/23.976fps, while 50Hz in Europe led to 25/50fps. For web delivery, either works, but mixing them on a timeline causes stuttering and audio sync issues. Most international co-productions shoot at 24fps for universal compatibility.
The 180 degree shutter rule is a cinematography guideline stating your shutter speed should be double your frame rate for natural-looking motion blur. The name comes from rotary disc shutters in film cameras, where a 180-degree opening exposes the film for exactly half the frame duration. At 24fps this gives 1/48s, at 25fps it gives 1/50s, and at 30fps it gives 1/60s. Breaking this rule creates distinct looks: a narrower angle (e.g., 90°) produces staccato, sharp movement like in Saving Private Ryan, while a wider angle (270–360°) gives dreamy, smeared motion blur.
23.976fps (often written as 23.98) exists because of NTSC color television. When color was added to the NTSC broadcast standard in the 1950s, the frame rate was slowed by a factor of 1000/1001 to prevent interference between the color subcarrier and audio frequencies. This gave 29.97fps for interlaced broadcast and 23.976fps for progressive cinema content. True 24.000fps is still used in theatrical DCP projection, but virtually all digital camera workflows use 23.976fps for NTSC compatibility.
Divide the playback frame rate by the capture frame rate and multiply by 100 to get speed percentage. For example: shooting at 120fps and playing back at 24fps gives (24 ÷ 120) × 100 = 20% speed, which is 5× slower. A 1-second real-time event captured at 120fps will play back over 5 seconds at 24fps. To find recording time needed: multiply the desired playback duration by (playback fps ÷ capture fps). For 10 seconds of 5× slow-mo at 24fps, you need 10 × (24 ÷ 120) = 2 seconds of recording.
Shutter angle describes exposure time as a proportion of the frame period, originating from rotary disc shutters in film cameras. A 360° angle means the sensor is exposed for the entire frame duration; 180° means half. Shutter speed is an absolute duration (e.g., 1/48s). The key advantage of shutter angle is consistency: a 180° angle always produces the same motion blur character regardless of frame rate, whereas a fixed shutter speed of 1/48s would look different at 24fps versus 60fps. Most cinema cameras display both options.
Match your shutter speed to a multiple of the electrical frequency. In 50Hz regions (Europe, most of Asia, Africa), use 1/50s, 1/100s, or 1/200s. In 60Hz regions (North America, parts of Japan), use 1/60s, 1/120s, or 1/240s. At 24fps, a 172.8° shutter angle gives exactly 1/50s for flicker-free shooting under 50Hz lighting. At 25fps, the standard 180° already gives 1/50s. LED lights may flicker at different frequencies than their power source, so always test with your specific fixtures.
For standard YouTube content, 24fps or 30fps are the most common. 24fps gives a cinematic look, while 30fps feels smoother and is preferred for talking-head videos, vlogs, and tutorials. For gaming content, 60fps is standard. If you plan to add slow motion in post, shoot B-roll at 60fps or 120fps and conform to your 24/30fps timeline.
At 60fps played back at 24fps, you get 2.5× slow motion (40% speed). At 30fps playback, you get 2× slow motion (50% speed). This is subtle slow motion, enough to smooth out action and add a slightly dreamy quality, but not dramatic. For more noticeable slow motion (5× or more), you need 120fps or higher capture rates.
Most narrative cinema is shot at 24fps (or 23.976fps for NTSC compatibility). European productions and broadcast content often use 25fps. High frame rate (HFR) experiments like The Hobbit used 48fps. For slow motion, cinema cameras like the RED V-Raptor can shoot up to 600fps at reduced resolution, and specialized cameras like the Phantom Flex4K can reach 1000fps at 4K.
Overcranking means shooting at a higher frame rate than playback speed, resulting in slow motion. The term comes from manually cranking film cameras faster. For example, shooting at 120fps and playing back at 24fps is overcranking. Undercranking is the opposite, shooting at a lower frame rate (e.g., 12fps played at 24fps) creates a sped-up, jittery look often used for comedy or chase sequences.
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