Every text and background pair scored against WCAG AA and AAA for normal and large text.
Build a linear, radial or conic gradient stop by stop with position sliders, then copy the CSS — which is re-parsed on the page to prove the output is valid.
Design a button's colours, padding, radius, border and shadow with a live preview, and get a measured WCAG contrast verdict on the text.
Build a complementary, analogous, triadic, split-complementary or monochromatic palette from one base colour, with the hue offsets shown and the best-contrast accent picked out.
Convert 1-3999 both ways, see how each numeral adds up and catch non-standard forms like IIII.
Test any number for primality with Miller-Rabin, then get its prime factorisation and every divisor.
Mean, median, mode, quartiles, range and standard deviation for any list of numbers.
Add tax to a net amount or strip it back out of a gross amount, with common rates one click away.
