Thermal Range Calculator

1Your sight or camera
2The object
3How much do you need to see?

The number of sensor pixels the object has to cover. More pixels means more detail, and a shorter range. These pixel counts are planning guidelines, not a guarantee.

IR.Tools targets with this sight

These are estimates. They assume ideal conditions: clear air, a target warmer or cooler than its background, and a sharp, focused image. Fog, rain, humidity, haze, and low thermal contrast all reduce real-world range. Digital zoom makes the picture bigger but does not add detail, so it is not part of the calculation.

Each result uses the more limiting of the sight's horizontal and vertical direction.