A depth of field calculator for photography. Choose your sensor size (full frame, APS-C, Micro Four Thirds, 1-inch, smartphone, or medium format) and the matching circle of confusion (CoC) is set for you. Then enter the focal length (mm), the f-number (aperture), and the focus distance, and it solves the near limit and far limit of acceptable sharpness, the total depth of field between them, how much of that depth falls in front of and behind the subject, and the hyperfocal distance (focus there and everything from half that distance to infinity is sharp). The focus distance can be entered in metres, centimetres, or feet. Stopping down (a larger f-number) and moving farther from the subject both increase depth of field; opening up (a smaller f-number) and moving closer make it shallower so the background blurs more. When the focus distance reaches or exceeds the hyperfocal distance, the far limit shows as ∞ (infinity). Use it to judge how much background blur you'll get for a portrait, which aperture keeps a landscape or product shot sharp front to back, or where the in-focus range falls for macro — all before you shoot. Every calculation runs in your browser; the numbers you enter are never sent to any server or API.