Terms of use

Last updated: October 20, 2026

Using the site

NineByNine is free to use. No account is needed. Please do not misuse the site or try to disrupt it, and do not download the puzzle files in bulk.

Puzzles and printables

You may play the puzzles and print them for personal use and for use in a classroom. Republishing puzzles, solutions or guides (for example in a book, app, newspaper or website) needs our permission: [to be provided].

The solver

You can use the solver on any puzzle you have the right to use. Puzzles from newspapers, books or apps belong to their publishers.

Your data

Your saved games, stats and settings are stored in your own browser. Clearing your browser data deletes them, and we cannot recover them. See the privacy policy.

Content and names

The text, puzzles and design belong to [to be provided] (owner). “Sudoku” is a registered trademark of Nikoli Co., Ltd. in Japan. NineByNine is not affiliated with Nikoli.

Availability

We aim to keep the site available and working correctly, but it is provided as is, without warranties.

Limitation of liability

[to be provided]

Governing law

These terms are governed by the laws of [to be provided].

Contact

[to be provided] (contact email)