How it works
A wireless heat map places a measured or predicted value on a floor plan using colours. It might show signal strength, signal-to-noise ratio, interference or throughput. The legend defines what the colours mean; two visually similar maps may represent different measurements and should not be compared as if they show the same thing.
Important differences and limits
A prediction depends on the model of walls, antennas and building materials. A measured map depends on survey positions and the device used. Unmeasured gaps may be interpolated rather than directly verified. A green coverage area does not prove adequate capacity for many simultaneous users or smooth roaming between access points.
A useful practical check
Check the scale, frequency band, metric and test conditions before drawing conclusions. Compare the map with the tasks that need to work, such as a video call in an office or a camera feed outdoors. Validate weak and important areas with actual client tests, and keep the floor plan and measurements current after network changes.
An example in practice
A signal-strength map may look reassuring while the same area performs poorly under interference. Compare the relevant metric and an application test before adding another access point. More equipment without channel planning can create overlap rather than solve the underlying problem shown by the measurements. Keep the legend with exported images, because colour alone cannot explain what was measured or predicted.