Accuracy and Disclaimer

Last updated 2026-08-14.

Use the results, but check them

SudokuElo is built to be accurate and is tested against known reference values. It is still software written by people, running in a browser we do not control, on input we cannot see. Treat every result as a well-informed starting point rather than an authority.

Before you rely on a result for anything that matters — money owed to someone, a legal or tax position, a medical decision, a machined part, a navigational fix — check it against a second source.

Specific limits of this site

Every puzzle published here is verified to have exactly one solution. The check is a solver that counts solutions and stops at two, run after each clue is removed during generation rather than once at the end — which is the difference between a puzzle that is unique and one that merely looks it.

Every puzzle is also verified to be solvable by reasoning alone, using only the techniques described on the level pages. Anything a human-technique solver could not finish was discarded during generation rather than relabelled as a harder level.

Difficulty is the hardest technique the puzzle forces you to use, not a count of its clues. That is a different measure from most Sudoku sites, so a puzzle labelled "hard" here will not necessarily match one labelled "hard" elsewhere, in either direction.

The solver page will tell you whether a puzzle from somewhere else has one solution, more than one, or none. That verdict is about the grid exactly as entered: a mistyped clue produces an honest verdict about a puzzle you did not mean to ask about.

Puzzles are generated in your browser using its own random number source. They are suitable for a newspaper page, a classroom or a waiting room. They are not certified random and must not be used where the fairness of a draw carries any weight.

Nothing you type into the solver is transmitted, and nothing is saved for you. Print a puzzle before you leave the page.

Not professional advice

Nothing on this site is educational or other professional advice, and using the Sudoku generator does not create a professional relationship of any kind. If a decision has real consequences, ask somebody qualified and accountable.

Liability

Our liability for the results this site produces is limited as described in the Terms of Service. In short: the site is free, it is provided as-is, and we cannot accept responsibility for losses caused by relying on it without checking.