Depth of Field Calculator
See exactly how much of your photo will be in focus, for any camera, lens and aperture.
Depth of Field Explained: A Complete Guide →
What is depth of field?
Depth of field (DoF) is the zone in front of and behind your focus point that still looks acceptably sharp. Everything inside that zone reads as in focus; everything outside it falls off into blur. It is not a hard edge but a gradual transition, which is why the limits are defined against a small blur circle called the circle of confusion.
Four things set the depth of field: the aperture, the focal length, how far away you focus, and the sensor size. This calculator combines all four and returns the near limit, the far limit, the total depth of field and the hyperfocal distance for your exact setup.
How aperture and focal length affect it
Aperture is the quickest control: a higher f-number (say f/11) deepens the zone of sharpness, while a wide aperture (f/1.8) makes it razor-thin. Depth of field changes roughly in proportion to the f-number.
Focal length has an even stronger pull because depth of field scales with the square of the focal length. A 24 mm lens holds far more in focus than an 85 mm lens at the same aperture and distance, which is why wide lenses suit landscapes and long lenses suit portraits with soft backgrounds.
Full frame vs APS-C vs Micro 4/3
At the same framing and aperture, a smaller sensor renders more depth of field. That is why phone cameras keep almost everything sharp and medium format throws backgrounds out so easily. The effect comes from the smaller circle of confusion and shorter focal lengths that small sensors use to match a given field of view.
Pick the sensor that matches your camera in the calculator so the near and far limits are correct for your format.
How this calculation works
Formula: H = f² / (N · c) + f
where:
f= focal lengthN= aperture (f-number)c= circle of confusion
Sources:
FAQ
Does aperture or focal length matter more?
Both matter, but focal length has a stronger effect: depth of field changes with the square of the focal length, while it changes roughly linearly with the f-number.
Which sensor should I pick?
Choose the one that matches your camera. Smaller sensors use a smaller circle of confusion, so they render more depth of field at the same framing and aperture.
How is depth of field calculated?
It uses the circle of confusion for your sensor together with focal length, aperture and focus distance to find the near and far sharp limits; the total is the distance between them.
Why is my background still not blurry?
For stronger background blur, open the aperture, move closer to your subject, use a longer lens, or put more distance between the subject and the background.