About the Depth of Field Calculator
This depth of field calculator tells you how much of your scene will look sharp. Enter the lens focal length, the aperture, the distance you are focused at and your camera’s sensor size, and it returns the nearest and farthest points that will appear acceptably sharp, the total depth of field, how much of it falls in front of and behind the subject, and the hyperfocal distance.
Portrait photographers use it to check that both eyes will be in focus at f/1.8, landscape photographers to make sure the foreground and the mountains are both sharp, and macro and product shooters to decide whether they need to stop down or focus-stack. The table repeats the calculation for every full-stop aperture from f/1.4 to f/22 so you can compare at a glance.
Results use the standard thin-lens formulas with a circle of confusion of 0.030 mm for full frame, scaled by the crop factor for smaller sensors (0.020 mm for 1.5× APS-C, 0.015 mm for Micro Four Thirds). That corresponds to a typical 8 × 10 inch print viewed at normal distance; pixel-peeping at 100% demands a smaller value, which you can enter as a custom circle of confusion.
How to use the depth of field calculator
- 1Enter the focal length of your lens (the real focal length, not the full-frame equivalent).
- 2Enter the aperture you plan to shoot at.
- 3Choose metres or feet and enter the distance to your subject.
- 4Select your camera’s sensor format, or enter a custom circle of confusion.
- 5Read the near and far limits, then use the aperture table to pick the f-stop you need.
Formula and method
The hyperfocal distance H is the closest focus distance at which the far limit of sharpness reaches infinity. From it, the near and far limits follow from the thin-lens equations, where s is the focus distance measured from the sensor. All lengths are worked in millimetres and converted back to metres or feet.
The circle of confusion c is the largest blur spot that still looks like a point in the final image. The calculator uses 0.030 mm for full frame (roughly the sensor diagonal ÷ 1440) and divides it by the crop factor for smaller sensors, because their images are enlarged more for the same print. Depth of field is not a hard edge — sharpness falls off gradually on either side of the focus plane.
- f
- Focal length (mm)
- N
- Aperture f-number
- c
- Circle of confusion (mm)
- s
- Focus (subject) distance (mm)
- H
- Hyperfocal distance (mm)
Worked examples
50 mm at f/2.8, subject at 3 m, full frame
With c = 0.03 mm, the hyperfocal distance is 50² ÷ (2.8 × 0.03) + 50 ≈ 29.81 m. The sharp zone runs from about 2.73 m to 3.33 m — roughly 0.60 m in total, with 0.27 m in front of the subject and 0.33 m behind it.
85 mm portrait at f/1.8 from 2 m on APS-C
APS-C uses c = 0.03 ÷ 1.5 = 0.02 mm, giving a hyperfocal distance of about 200.8 m. At 2 m the sharp zone is only about 4 cm deep (1.981 m to 2.019 m), so focus precisely on the nearest eye.
Landscape: 24 mm at f/11 focused at 10 ft
At f/11 the hyperfocal distance of a 24 mm lens on full frame is about 5.81 ft. Focusing at 10 ft is beyond that, so everything from about 3.66 ft to infinity is acceptably sharp.
Frequently asked questions
What affects depth of field?+
Three things: aperture (smaller apertures such as f/11 give more depth), focus distance (closer subjects give much less depth) and focal length at a given distance. Sensor size matters indirectly through the circle of confusion and the focal length you need for the same framing.
What circle of confusion should I use?+
The common standard is 0.030 mm for full frame, 0.020 mm for 1.5× APS-C, 0.019 mm for Canon APS-C and 0.015 mm for Micro Four Thirds. For large prints or viewing at 100% on screen, halve these values for a stricter result.
What is the hyperfocal distance?+
It is the focus distance that makes the far limit of sharpness reach infinity. Focusing there keeps everything from half the hyperfocal distance to infinity acceptably sharp, which maximises depth of field for landscapes.
Is depth of field split one-third in front and two-thirds behind?+
Only at moderate distances. Close up, depth of field is split nearly evenly in front and behind the subject; as you approach the hyperfocal distance the zone behind the subject grows towards infinity.
Why is my depth of field so shallow at close range?+
Depth of field shrinks roughly with the square of the focus distance, so halving the distance cuts it to about a quarter. In macro work it can be under a millimetre, which is why photographers use focus stacking.