Inclinometer or scoliometer is an instrument used by topography, aviation and ships to measure the inclination of the plane with respect to the horizontal (earth's surface).

In naval terms, the inclinometer allows measuring the degree of heel of a ship with respect to its radial axis or the degree of longitudinal or axial inclination (degree of snout in Spanish naval terms).

In the topographic aspect, surveyors can measure the angle of inclination of the terrain with respect to the horizontal plane of the Earth using a terrain inclinometer, in order to model the terrain studied.[1]​.

In the aeronautical industry, the inclinometer allows the pilot to know the position of the wings with respect to the false horizon of the instrument.

Inclinometers are also widely used in motorsports, especially in offroad or all-terrain vehicles.[2]​.

There are several principles for constructing an inclinometer, some of which are based on the deformation of a steel rod that experiences torsion with respect to the inclination to which it is subjected.[3]​

Other inclinometers are based on a free ballast that acts by the action of the gravitational force. Others are based on the displacement of an air bubble in a confined liquid medium (level gauge).