Free Shutter Angle Calculator

In video, shutter speed is described as an angle. The cinematic standard — the 180° rule — sets the shutter to 1/(2 × frame rate): 1/48 s at 24 fps, 1/60 s at 30 fps, 1/120 s at 60 fps. That's the natural motion blur your eye expects.

Angle → speed

Frame rate (fps)

Shutter angle (°)

Result

Shutter speed

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for this angle

180° speed

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the cinematic reference

🎬 Reading: at fps the 180° shutter is . Set this and motion looks natural. Go wider (270–360°) for dreamy blur, narrower (90–45°) for crisp, staccato motion — but stay near 180° for the "film look".

Common frame rate × angle table

FPS	360°	270°	180°	90°	45°
24	1/24 s	1/32 s	1/48 s	1/96 s	1/192 s
25	1/25 s	1/33 s	1/50 s	1/100 s	1/200 s
30	1/30 s	1/40 s	1/60 s	1/120 s	1/240 s
50	1/50 s	1/67 s	1/100 s	1/200 s	1/400 s
60	1/60 s	1/80 s	1/120 s	1/240 s	1/480 s
120	1/120 s	1/160 s	1/240 s	1/480 s	1/960 s

Shutter angle FAQ

Why 180 degrees?

Shutter angle describes how long the shutter stays open per frame, as a fraction of a full rotation. At 180° it's open half the frame time, giving motion blur that matches how the eye tracks movement — too open (360°) blurs, too closed (45°) stutters.

What shutter speed for slow motion?

Same rule: 1/(2 × fps). At 120 fps that's 1/240 s. Many cameras auto-set this when you select 180° in video mode — check your menu.

Does the 180° rule apply to stills?

No — stills use shutter speed directly (1/focal length or faster for handheld). The angle system is a video/cinema convention, though the motion-blur logic is the same.