Shutter speed calculator
Find the minimum handheld shutter speed for your lens using the reciprocal rule - adjusted for your sensor\'s crop factor and, optionally, a high-resolution safety margin.
Setup
Use 1.5×–2× as a safety margin on 40MP+ sensors where shake is easier to see.
Result
Minimum handheld shutter speed
Stabilisation and subject motion change reality - see below.
How it works
The reciprocal rule is the classic starting point for blur-free handheld photos: never shoot slower than 1 / effective focal length. The “effective” length is your real focal length multiplied by the crop factor, because a smaller sensor magnifies both the subject and your shake. A resolution safety factor is applied on top when pixels are so dense that tiny shake becomes visible:
Example
An 85 mm lens on a 1.5× APS-C body behaves like 127.5 mm. The rule gives 1/127.5 s as the slowest safe speed, so you shoot the nearest faster standard - 1/160 s or faster. With a 2× safety factor on a high-resolution body that becomes 1/255 s → 1/320 s.
Why this is only a starting point
- Stabilisation (IBIS or lens VR) reliably buys 3–5 stops, letting you shoot far slower than the rule.
- Subject motion is not camera shake: a walking person needs around 1/250 s and a car needs 1/1000 s regardless of your lens.
- Your technique - breathing, bracing and shutter technique - shifts the real threshold by a stop or two either way.
Related tools
Once your shutter speed is set, balance the rest of the triangle with the exposure triangle calculator. Shooting long exposures on a tripod? Plan them with the long exposure calculator and see the focal-length relationship in the focal length calculator.
Frequently asked questions
What is the reciprocal rule?
It says your minimum handheld shutter speed is 1 over the effective focal length. For a 50 mm lens on a 1.5× APS-C body the effective length is 75 mm, so the rule suggests 1/75 s or faster - in practice usually rounded to 1/80 s or 1/100 s.
Why does my camera crop factor matter for handheld shooting?
A smaller sensor crops into the image circle, so camera shake is magnified along with the subject. Multiplying the focal length by the crop factor gives the full-frame-equivalent reach, and the reciprocal rule should use that number.
Do high-resolution cameras need faster shutter speeds?
Often yes. With more pixels the same angular shake is resolved into more pixels of blur, so many photographers apply a safety factor of 1.5–2× on 40MP+ bodies - treat it as a starting point, not a guarantee.
Does image stabilisation remove the need for the rule?
Stabilisation can let you handhold several stops slower, but it does not freeze subject motion - moving subjects still need a shutter speed set by their speed, not by your steadiness.