Handheld Shutter Speed Checker
Find the slowest shutter speed you can hand-hold for a given lens and sensor, adjusted for image stabilization.
This covers camera shake only. Moving subjects need their own speed regardless of stabilization: roughly 1/250 s for a walking person, 1/1000 s or faster for sports. Higher resolution sensors also show shake more readily, so lean toward the safe side.
How it works
The reciprocal rule is a shorthand for the slowest shutter speed you can hand-hold before your own body movement blurs the shot. The classic version says your shutter speed should be at least 1 over your focal length in millimeters, so a 50mm lens wants at least 1/50 s. Crop sensors make this stricter because the same lens covers a narrower field of view, which is the same as using a longer effective focal length, so the calculator multiplies by the sensor's crop factor. A 50mm lens on an APS-C body (1.5x crop) needs 1/75 s, not 1/50 s.
Image stabilization, whether it lives in the lens or the camera body, buys you back some of that safety margin. Each stop of stabilization roughly halves the shutter speed you need, so 3 stops on that same 1/75 s number brings the safe speed down to about 1/9 s worth of shake correction, meaning you could actually go as slow as roughly 1/25 s and still expect a sharp result. Worked example: a 200mm lens at full-frame with no stabilization wants 1/200 s or faster; add 3 stops of stabilization and that drops to 1/25 s.
FAQ
Does this rule account for a moving subject?
No. The reciprocal rule only fights your own hand shake. A stationary subject like a building or a posed portrait is fine at the calculated speed, but a walking person needs roughly 1/250 s to freeze motion cleanly, and fast sports or wildlife action often needs 1/1000 s or faster regardless of what stabilization gives you.
Do higher megapixel cameras really need faster shutter speeds?
Yes, in practice. A higher resolution sensor shows shake more clearly when you zoom into the pixels, so photographers with 40+ megapixel bodies often add half a stop or a full stop of safety margin on top of the basic reciprocal rule.
Should I trust image stabilization ratings printed on the box?
Treat manufacturer stop ratings as a best-case number measured under ideal test conditions. Real-world results depend on your hand steadiness, how you brace the camera, and whether you're breathing hard after a hike. Dialing in one or two fewer stops than advertised is a safer starting point.
Is there a downside to just using a faster shutter speed than the minimum?
Only that a faster shutter lets in less light, so you'll need a wider aperture or higher ISO to keep the same exposure. In good light this costs nothing. In dim conditions it's a real tradeoff between a guaranteed sharp shot and one with a shallower depth of field or more visible noise, so treat the reciprocal rule as a floor, not a target to beat by a wide margin.
For more on shutter speed fundamentals, see our shutter speed explainer, whether you need a tripod, and night photography for beginners.