Accessibility

This site targets WCAG 2.2 Level AA. That is a commitment about how it is built, not a certification anyone issued.

What that means in practice

• Every page works with a keyboard alone, in a logical order, with a focus indicator you can see.
• Every form control has a real label, not a placeholder standing in for one.
• Calculator results are announced politely to a screen reader as they change, without moving focus away from the field being typed into.
• Text contrast is at least 4.5:1, and interface borders at least 3:1, in both themes.
• Touch targets are at least 44 by 44 pixels.
• Animation is suppressed when the system asks for reduced motion.
• Every reference table is rendered as real HTML with proper header cells, not as an image.

How it was tested

Automated checks run on every build: HTML validation including WCAG-specific rules, and a Lighthouse accessibility audit that fails the build below 95. Contrast ratios are recomputed from the design tokens by a unit test, so a colour change that breaks contrast fails rather than shipping. Keyboard operation of the calculators is covered by end-to-end tests.

Automated testing catches a minority of accessibility problems. If you hit something these checks missed, please report it.

Known limitations

The three self-hosted typefaces cover Latin scripts only. Pages in Hindi, Japanese and Arabic fall back to the system font stack for those scripts, which renders correctly but does not match the Latin pages typographically.