Which black dot is bigger? Or are they actually the same? This is an example of a Delboeuf illusion which uses surrounding rings to alter your perception of the relative size of the inner circles. Find a range of awesome optical illusions here at Kids Math Games Online. Enjoy free pictures and images that deceive the eye and are sure to put your brain to work.
To save this cool optical illusion simply right click on the picture and select 'save image as'.