Accessible Sudoku: Contrast, Colorblind-Safe and Text Size Options

Updated 15 October 2026

Accessibility in Suuudokuuu is a set of settings you can combine, not a separate game. This page lists what the app actually offers, so you can tell before you install whether it fits how you play.

Colorblind-safe and high-contrast themes

The Colorblind safe theme tells board states apart by lightness and outlines instead of hue, so a highlighted cell, a pattern and a mistake do not depend on telling red from green. The High contrast theme maximises the separation between board states. Both are in Settings under Theme, next to Classic, Gold and Newspaper. If none of them fits, the live-preview theme editor lets you set every cell, line and highlight yourself, with built-in contrast validation so a custom theme stays readable.

Digit size and cell spacing

Number size has four steps, Tiny, Small, Standard and Large, and Cell spacing has three, Tight, Comfortable and Spacious. The Spacious setting adds wider gaps for easier tapping. Both are in Settings under Game.

Motion and feedback

The Animations setting can follow your device, stay always on or be always off, in which case changes appear instantly. The timer and vibration each have their own switch, and Calm play hides the score. See relaxing sudoku for those options in context.

Screen readers

Every board cell is exposed as a button with a label that says whether it is empty, what it holds, and whether it is marked wrong. The number pad digits, the notes toggle, undo, redo, hint and auto-candidates controls are labelled too, and hint text is announced as it changes. On the web the board is a labelled grid you can move through with the keyboard; the keyboard shortcuts page lists the keys.

OS text scaling

Text in the app respects the text size you set in iOS or Android, with a cap so that layouts stay usable, at most twice the normal size for body text and less for tight elements such as the tab bar. This is separate from the Number size setting, which only changes the digits on the board.

On this website

The header of every page here has a text-size control, A, A+ and A++, that scales the whole page including boards and remembers your choice. For paper, the large-print booklet uses bigger grids, and the sudoku for seniors page collects the comfort settings in one place.