Optical illusions
Seven classics. Each one is drawn by this site and measured from its own pixels.
Café wallLevel lines with a false tilt.
Hermann gridGray smudges at crossings of pure white.
Müller-LyerTwo equal lines. One looks longer.
ZöllnerParallel lines leaning toward each other.
EbbinghausSame disc, different neighbors.
PonzoTwo equal bars between converging rails.
Simultaneous contrastThe same gray looks lighter on dark and darker on light.
What to expect on each page
You get a live demo with one slider, a short explanation, the numbers measured from the image and a table showing where the effect weakens. A second page for each illusion gives you every slider and a PNG download.
The images are original. None is a copy of a famous artwork. Want to build one now? Open the illusion maker.