Every point where Gauss Labs measured the field of each common coil type, drawn where it sits on the coil. Pick a coil type and a distance from the surface, then hover over a point (or tap it) to read its Gauss value. The mat is a modeled example; the loop, pancake and donut are real measurements.

A six-coil mat. Each coil makes its own hot spot; the values are modeled from the mat's coil layout rather than probed.