Tools / Sensor format
Sensor Format Calculator
Pixel count × pixel pitch gives the exact active area. Optical-format names only describe a size class, so use them when you do not have the sensor datasheet yet.
This sensorNearby standard formats (to scale)
Common optical formats
The inch names come from the outer diameter of old vidicon camera tubes, not from the sensor itself. As a rule of thumb, a format of 1/2″ or larger has about 16 mm of diagonal per inch, and smaller formats about 18 mm. Sizes below are nominal 4:3 active areas; many 16:9 security sensors share a type name with the same diagonal but a wider, shorter shape.
| Type | Width × height | Diagonal | Crop factor |
|---|
Formulas
Active area from pixels: W = Nx · p, H = Ny · p, diagonal d = √(W² + H²). Crop factor is 43.27 mm / d, the full-frame diagonal over this sensor's diagonal; multiply a focal length by it to get the 35 mm equivalent field of view.
Estimated optical format: for d ≥ 8 mm the type is about d / 16 inch, and below that about d / 18 inch, written as 1/x″. Manufacturers round these names, so treat the estimate as the format a datasheet would most likely print.
Background reading: Why a 1/2.8″ sensor is not 1/2.8 inch