Photography Tool

Crop Factor Calculator

Find the equivalent focal length and aperture for any sensor size: full-frame, APS-C, Micro Four Thirds, medium format, and more.

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Sensor Size

Focal Lengthmm

Common

Aperturef/

Common

Results

Crop Factor: 1.53×
Equivalent Focal Length: 76.6mm
Equivalent Aperture: f/4.3

Your sensor sees the highlighted area (1.53×)

Common cameras and their crop factors

Quick reference for popular mirrorless and DSLR bodies, grouped by sensor format. Crop factors here are the manufacturer-quoted figures (based on sensor diagonal). The calculator above uses sensor width, so you'll see a tiny rounding difference on 4:3 formats like medium format and Micro Four Thirds.

Sensor format	Crop factor	Example bodies
Medium Format (44×33mm)	0.79×	Fujifilm GFX 100 II, Fujifilm GFX100S II, Hasselblad X2D 100C
Full Frame (36×24mm)	1.0×	Sony α7 IV / α7R V / α1 II, Canon EOS R5 Mark II / R6 Mark II / R1, Nikon Z6 III / Z8 / Z9, Panasonic Lumix S5 II
APS-H (28.7×19mm)	1.3×	Canon EOS 1D Mark IV, Leica M8
APS-C — Nikon / Sony / Fuji / Pentax	1.5×	Fujifilm X-T5 / X-H2S / X100VI, Sony α6700 / ZV-E10 II / FX30, Nikon Z50 II / Zfc / Z30
APS-C — Canon	1.6×	Canon EOS R7, Canon EOS R10, Canon EOS R50
Micro Four Thirds (17.3×13mm)	2.0×	OM System OM-1 Mark II, Panasonic Lumix GH7, OM System OM-5
1-inch (13.2×8.8mm)	2.7×	Sony RX100 VII, Canon PowerShot G7 X Mark III

By brand

Canon
Full-frame: 1.0× · APS-C: 1.6× · APS-H: 1.3× (older pro bodies)
Nikon
Full-frame (FX): 1.0× · APS-C (DX): 1.5×
Sony
Full-frame: 1.0× · APS-C: 1.5× · 1-inch (RX100): 2.7×
Fujifilm
Medium format (GFX): 0.79× · APS-C (X-mount): 1.5×
OM System / Panasonic
Micro Four Thirds: 2.0× · Panasonic full-frame (S): 1.0×
Pentax / Ricoh
Full-frame (K-1): 1.0× · APS-C (K-3): 1.5×

How crop factor actually works

Crop factor is the ratio between a camera's sensor and a 35mm reference frame (36×24mm). A smaller sensor captures a narrower slice of what a lens projects, so the image looks more tightly framed. The factor itself is just a multiplier: divide 36mm by your sensor's long edge and you've got it. Nikon's APS-C sensor is 23.5mm wide, so 36 ÷ 23.5 ≈ 1.53×.

Focal length (field of view)

Crop factor multiplies the apparent focal length. A 50mm lens on APS-C (1.5×) frames like a 75mm would on full-frame. The lens itself hasn't changed; you're just seeing a smaller patch of its image circle. Perspective stays the same, since that's a function of subject distance.

Aperture & depth of field

Aperture matters in two ways. For exposure, f/2.8 is f/2.8 on any sensor: same shutter, same ISO, same brightness. For depth of field and background blur, a smaller sensor at the same aperture gives a deeper DoF. f/2.8 on APS-C looks roughly like f/4 on full-frame, which is the "equivalent aperture" number this calculator shows.

ISO & exposure — a common myth

Crop factor does not change your exposure, and it does not multiply ISO. f/4 at 1/200s at ISO 400 produces the same brightness on full-frame, APS-C, or Micro Four Thirds. What does differ is the total light collected across the whole frame, which is why larger sensors tend to have cleaner high-ISO files. That's a noise question, not an exposure one.

Video: extra crop to watch

Some cameras add an extra crop in video mode, especially in 4K or 60p. A full-frame body might shoot stills at 1.0× but record 4K at 1.5× or tighter. Always check the specs for each recording mode before buying wide lenses for video.

Frequently asked questions

How do I calculate crop factor?

Divide the width of a 35mm full-frame sensor (36mm) by the width of your camera's sensor. A Canon APS-C sensor is 22.3mm wide, so 36 ÷ 22.3 ≈ 1.6×. The calculator above does this for you and also shows the equivalent focal length and aperture.

Does crop factor make my lens longer?

Not physically. A 50mm lens is always a 50mm lens. What changes is the field of view the sensor captures: a crop sensor records a smaller rectangle out of the image the lens projects, so the scene looks more zoomed-in than it would on full-frame. You genuinely get more reach for wildlife. But the lens isn't becoming a different lens; you're just looking at a tighter crop of what it sees.

Does crop factor affect aperture or ISO?

Exposure doesn't change. f/2.8 and ISO 400 behave the same on every sensor. Depth of field does change: a smaller sensor at the same f-number gives a deeper DoF, which is where "equivalent aperture" comes in. Noise is a separate story from ISO itself; larger sensors tend to be cleaner at a given ISO because they collect more total light, but crop factor never multiplies the ISO number itself.

Is a crop sensor worse than full-frame?

They're different tools, not ranked ones. Crop sensors are smaller, lighter, cheaper, and give you more effective reach at the telephoto end. Full-frame gives you a wider native field of view, shallower depth of field for the same framing, and a bit more low-light headroom. Wildlife and reach-hungry shooters often prefer APS-C; portraitists and astrophotographers often prefer full-frame.

What's the crop factor in 4K video?

It depends on the camera. Some bodies shoot 4K using the full sensor width; others read a smaller area and apply an extra crop (often 1.3–1.8× on top of the sensor's still-mode crop factor). Check your camera's spec sheet under "4K recording area" or similar.

Do mirrorless cameras have different crop factors than DSLRs?

No. Crop factor is a property of the sensor, not the mount or mirror. A Sony α6700 (mirrorless) and a Nikon D7500 (DSLR) both have 1.5× APS-C sensors and behave identically for crop factor. Mirrorless and DSLR differ in autofocus, size, weight, and lens availability, but the sensor math is the same.

Can I use a full-frame lens on a crop-sensor body (or vice versa)?

Full-frame lens on a crop body: yes, and the crop factor applies. A 50mm full-frame lens on APS-C behaves like a 75mm. You lose nothing optically; you're just using the sharpest center portion of the image circle. The other way around is trickier. Crop-sensor lenses (Canon EF-S, Nikon DX, Sony E APS-C, Fuji XF) project a smaller image circle, so on a full-frame body they'll either vignette heavily or trigger an automatic crop mode in the camera.

Do speed boosters and focal reducers change crop factor?

Yes. A focal reducer (for example, the Metabones Speed Booster) is an adapter with optical elements that compresses the image circle from a larger-format lens onto a smaller sensor. A typical 0.71× reducer turns a 1.5× APS-C crop into roughly 1.07×, close to full-frame, and gains about a stop of light along the way.