Hyperfocal Distance Calculator

Background.

The hyperfocal distance is the shortest distance you can focus at and still have the far limit of acceptable sharpness reach infinity. Focus there and everything from half that distance to the horizon falls inside your sharpness tolerance — the single most useful focusing shortcut in landscape, architecture and street photography. This calculator returns it from three things you already know: your sensor format, the focal length engraved on the lens, and the f-number you are shooting at.

It also answers the question the other way round, which is usually the one you actually have in the field. You are not normally choosing an aperture and then asking where to focus; you are looking at a rock two metres in front of you, deciding it has to be sharp, and asking how far you need to stop down. Switch the first dropdown to "f-number needed for a target near limit", type in that near distance, and the page inverts the identity for you. It works because focusing at the hyperfocal distance puts the near limit at exactly half of it, so a target near limit of 1.5 m simply means a hyperfocal distance of 3 m, and the f-number follows.

Every hyperfocal number depends on an assumption most calculators hide: the circle of confusion, the largest blur disc on the sensor that a viewer will accept as a point. It is a viewing-conditions decision, not a property of the lens. This page uses the convention published by Carl Zeiss in their technical article on depth of field and bokeh — the sensor diagonal divided by 1500, which is 0.0288 mm on full frame and matches the 0.03 mm figure the industry has used since the film era. A stricter option divides the diagonal by 3000, which the same paper calls the strictest sensible requirement, for when you will inspect the file at 100 % or print very large. Choosing it roughly doubles the hyperfocal distance. The value actually used is reported as an output so you can trace any disagreement with another calculator rather than guess at it.

The page also reports something most hyperfocal calculators leave out, and it is the number that justifies the whole technique: the near limit you would get by simply racking the lens to its infinity stop instead. That comes out at exactly H minus the focal length, which is about twice as far away as the hyperfocal near limit. In other words, hyperfocal focusing buys you a factor of two in usable foreground for no cost in aperture, shutter speed or ISO. If the two numbers look close together on your settings, the technique is not worth the fiddling; if they are far apart, it is.

There is a physical picture behind the algebra, and Zeiss's derivation makes it unusually clear. The entrance pupil of a lens has diameter f divided by the f-number. Light arriving from an infinitely distant point enters as a parallel bundle exactly that wide. The hyperfocal distance is simply the distance at which the acceptable object-side blur circle has grown to the same diameter as that entrance pupil — which is why the entrance pupil is reported here as an output too, and why the front edge of the sharp zone sits geometrically at the halfway point.

Below the widget you will find the exact equations with the focal-length term retained, a worked 24 mm f/11 example computed by hand at twenty significant digits, why the traditional infinity-focus habit costs you half your foreground, where the thin-lens model stops describing real internally-focusing lenses, and why stopping down past the aperture this page suggests will start to cost you sharpness to diffraction rather than gain it.

What is hyperfocal distance calculator?

The hyperfocal distance H is the nearest focus distance whose depth of field extends to infinity. It is set by three quantities: the focal length f, the f-number N, and the circle of confusion c — the largest blur diameter on the sensor that will still read as a point under stated viewing conditions. The relation is H = f²/(N·c) + f. Carl Zeiss's technical article on depth of field and bokeh derives it from first principles in three steps: the entrance pupil has diameter EP = f/N; a bundle of light from an infinitely distant point is parallel and therefore exactly EP wide; and the hyperfocal distance is the distance at which the acceptable object-side circle of confusion has grown to equal EP. Since object-side and image-side blur are related by the magnification M ≈ Dist/f, that gives Dist ≈ f²/(z'·k) in Zeiss's notation, where z' is the circle of confusion and k the f-number. The trailing + f in the version used here is the exact form and matters only at macro distances. Two consequences follow exactly, not approximately, from the standard near-limit expression Dn = s(H − f)/(H + s − 2f). Focus at s = H and the near limit becomes H(H − f)/(2(H − f)) = H/2 — Zeiss's own statement that "the front end of the depth of field is located at half of the hyperfocal distance". Focus at infinity instead and the near limit becomes H − f. Everything on this page is a thin-lens, symmetric-pupil model with distances measured from the front principal plane, and it describes defocus blur only: it says nothing about diffraction, field curvature or focus breathing, all of which can make the real result worse than the calculated one.

How to use this calculator.

1. 01Choose the question. Use "hyperfocal distance for a given f-number" when you have already picked an aperture. Use "f-number needed for a target near limit" when the foreground dictates the shot — that is the field workflow.
2. 02Pick your sensor format. This sets the circle of confusion and is the single most consequential choice on the page. If your camera is not listed, choose Custom and enter the imaging-area width and height in millimetres from your camera's specification sheet.
3. 03Enter the focal length engraved on the lens, in millimetres, not the 35 mm equivalent. The sensor selection already handles the format difference, so entering an equivalent would apply the crop factor twice.
4. 04In hyperfocal-distance mode, enter the working f-number: 11 for f/11, 5.6 for f/5.6. In target-near-limit mode, enter instead how close the nearest object that must be sharp actually is, in metres — measure or pace it rather than guessing.
5. 05Choose the sharpness standard. Use Standard for prints and normal screen viewing; use Critical if you will pixel-peep at 100 % or print beyond about A2. Critical roughly doubles the hyperfocal distance, so it is a meaningful decision, not a formality.
6. 06Focus at the hyperfocal distance the page returns. Since almost no modern lens has a usable distance scale, the practical method is to autofocus on something you can range at about that distance — a person, a fence post, a stretch of path — then switch to manual so the camera cannot refocus.
7. 07Check the near limit. Everything from that distance to the horizon is inside tolerance. Compare it with the "near limit if you focus at infinity" figure to see exactly what the technique is buying you on these settings.
8. 08Round the f-number up, not down, when the page solves for it. Lenses click at whole or third stops, and the calculated value is a minimum. But do not chase the last stop: past roughly f/11 on full frame, f/8 on APS-C and f/5.6 on Micro Four Thirds, diffraction starts to soften the whole frame faster than the extra depth of field helps.

The formula.

Work in millimetres throughout, then convert once at the end.

First the circle of confusion:

c = sensor diagonal / 1500 (standard, print viewing) c = sensor diagonal / 3000 (critical, 100 % inspection)

Full frame's diagonal is √(36² + 24²) = √1872 = 43.266615 mm, so c = 0.0288444 mm standard and 0.0144222 mm critical. Carl Zeiss's own depth of field charts are labelled "Format 24 x 36, z = 0.029 mm, D/1500", which is the same number, and the accompanying text states that 1/1500 of the diagonal "corresponds approximately to the often used 0.03 mm circle of confusion for the 35 mm format".

Then the hyperfocal distance:

H = f² / (N · c) + f

The derivation is physical, not algebraic. The entrance pupil has diameter EP = f/N. A bundle of rays from an infinitely distant point arrives parallel, so its diameter at the lens is exactly EP. Zeiss: "The hyperfocal distance is therefore the distance where the acceptable object-side circle of confusion diameter is as large as the entrance pupil." Object-side blur Z and image-side blur c are linked by the magnification M ≈ Dist/f, so setting Z = EP gives Dist ≈ f²/(c·N). The + f term is the exact correction and is negligible beyond a few hundred focal lengths.

The two companion results are exact consequences of the standard near-limit expression Dn = s(H − f)/(H + s − 2f):

focus at s = H → Dn = H(H − f) / (2H − 2f) = H/2 focus at s = ∞ → Dn = H − f

The first is the classic result. The second is the one worth internalising: racking to infinity is not a small compromise, it costs you a factor of two in foreground, every time. On a 24 mm f/11 full-frame shot that is the difference between sharp from 0.92 m and sharp from 1.82 m.

Inverting for the f-number is then trivial. A target near limit x implies H = 2x, and

N = f² / ((H − f) · c)

Note what this equation does and does not promise. It gives the aperture at which x is exactly on the edge of tolerance, so it is a minimum, not a recommendation — round up to the next marked stop. It also assumes you will actually focus at H; focusing anywhere else invalidates it.

The scaling laws follow directly. H goes as f², so doubling the focal length quadruples the hyperfocal distance — this is why wide lenses make hyperfocal focusing practical and long lenses make it useless. H goes as 1/N, so every stop down halves it. And H goes as 1/c, so a format with half the diagonal has half the hyperfocal distance at the same focal length; combine that with the shorter lens a small format needs for the same framing and the small-format hyperfocal distance collapses, which is why phone cameras behave as though everything past a metre is in focus.

What the model leaves out: diffraction, which past roughly f/11 on full frame softens the entire frame including the plane of focus; field curvature, which means the sharp zone is not a flat slab; pupil magnification, which shifts the effective aperture on strongly asymmetric designs; and focus breathing on internally-focusing lenses, whose focal length shortens as they focus closer. A hyperfocal figure is a planning number with a tolerance, not a guarantee — which is why many landscape photographers deliberately focus slightly beyond H, trading a little foreground for certainty at infinity.

A worked example.

Frequently asked questions.

References& sources.

1. [1]Nasse, H. H. (2010). 'Depth of Field and Bokeh.' Carl Zeiss Camera Lens Division. Derives the hyperfocal relation used here: EP = f'/k, 'The hyperfocal distance is therefore the distance where the acceptable object-side circle of confusion diameter is as large as the entrance pupil', M ≈ Dist/f', hence Dist_hyperfocal ≈ f'²/(z'·k); and states 'Looking at the cones of light we can easily see that the front end of the depth of field is located at half of the hyperfocal distance.' The same paper gives the circle-of-confusion convention: '1/3000 of the picture diagonal is the strictest sensible requirement... A circle of confusion twice as large, 1/1500 of the diagonal, viewed at a visual angle of 2 arc minutes, still provides a satisfying sharpness... this requirement corresponds approximately to the often used 0.03 mm circle of confusion for the 35 mm format.'
2. [2]Canon Inc. EOS R6 Product Manual, Specifications — Image Sensor. Gives the full-frame sensor size as 'Approx. 35.9×23.9 mm', the measured dimension behind the nominal 36 × 24 mm 135-format frame used for the full-frame preset.
3. [3]Nikon Corporation. D7500 Online Manual, Technical Notes — Specifications. Gives the Nikon DX imaging area as '23.5 × 15.7 mm CMOS sensor' and states that DX lenses are 'equivalent to approx. 1.5×' the 35 mm-format angle of view, the cross-check used to validate the diagonal-derived circle of confusion for that preset.
4. [4]Canon Inc. EOS R7 Product Manual, Specifications. Gives the Canon APS-C sensor size as 'Approx. 22.3 × 14.8 mm' and the angle-of-view conversion as 'Approx. 1.6 times the focal length indicated on the lens'.
5. [5]OM Digital Solutions. OM SYSTEM OM-1 Mark II Specifications, Image Sensor. Lists 'Aspect ratio & area 4:3 / 17.3 x 13.0 mm' for the Four Thirds imaging area used by the Micro Four Thirds preset.
6. [6]FUJIFILM Corporation. GFX100 II Specifications. Lists the image sensor as '43.8mm×32.9mm', the dimensions used for the medium-format preset.
7. [7]Ray, S. F. (2002). Applied Photographic Optics: Lenses and Optical Systems for Photography, Film, Video, Electronic and Digital Imaging, 3rd ed. Focal Press. Standard reference for the exact near-limit expression Dn = s(H − f)/(H + s − 2f), from which both Dn(H) = H/2 and Dn(∞) = H − f are derived, and for the pupil-magnification correction this thin-lens model omits.