Privacy Policy

Last updated 14 October 2026

Ascendoku is a free sudoku game run as a personal, non-commercial project from Finland. This page explains exactly what it stores about you and what you can do about it. There is no advertising and no tracking: we count visits without cookies and without knowing who you are, and your data is never sold or shared for marketing.

What we collect

If you don't sign in, we keep no account or profile for you. Your unfinished puzzles stay in your own browser, and the pages you have solved are remembered in a cookie on your device. The only things that reach our servers are feedback you choose to send, crash reports and visit counts, all described below.

If you create an account, we store:

• Your email address, so you can sign in.
• Your name and email from Google, if you choose to sign in with Google. We never receive your Google password, and we ask for nothing beyond your name and email address.
• A display name, if you set one. This is visible to other players on leaderboards.
• Your gameplay: which puzzles you have solved, how long you took, experience points, level, rating, streaks, badges, campaign progress, friend connections and duel results.
• Puzzles you have started but not finished, so you can continue them on another device.

Feedback. If you send a note, we store your message, the page you sent it from, and a contact address only if you give one. A thumbs-up or thumbs-down on a puzzle is stored with a one-way code made from your account or internet address, so the same person can't vote twice; the address itself is not stored.

Crash reports. When something breaks, an error report goes to Sentry: what went wrong, on which page, and your browser and device type. We don't attach your name, email address or account to it.

Visit counts. To know whether anyone finds the site and how, we use Vercel Web Analytics. When a page loads it records the page's address (without anything after a “?”), the site that linked you here, your country, and your browser, operating system and device type. It sets no cookies and stores nothing on your device. Visitors are told apart by a code worked out from the request that resets every 24 hours, so a visit cannot be linked to you, to your visits on other days, or to other websites. We also keep a running total of how many puzzles are solved each day without an account: a number per day, with nothing about who solved them.

We do not collect your address, phone number, date of birth or payment details, because the game does not need them and there is nothing to pay for.

Why we're allowed to store it

Under the GDPR, we process this data to provide the service you asked for — you cannot have an account, a streak or a leaderboard place without a record of them. Your display name and scores appear on public leaderboards because that is the point of a leaderboard; if you would rather not appear, don't set a display name, or delete your account.

The visit counts rest on our legitimate interest in knowing whether the site is used and where its visitors come from. They are statistics only and cannot identify you. On the same basis we look at account records as totals, such as how many new players solve another puzzle in their first week, to see whether the game is working. Those totals are for us alone and are never published or shared.

Who else handles it

Ascendoku is built on a few services that necessarily process data on our behalf:

• Supabase — the database and sign-in system that stores your account and progress.
• Vercel — hosts the website, serves it to your browser, and provides the visit counts described above.
• Resend — sends your sign-in emails.
• Google — only if you choose “Continue with Google”.
• Sentry — receives the crash reports described above.

Each of these acts only on our instructions. Nobody else receives your data, and we do not sell it.

Cookies

Our cookies only make the game work: one keeps you signed in, and a few remember your place without an account (the pages you have solved, the hints you have used, and the book you last opened). There are no advertising, analytics or tracking cookies, which is why you are not being nagged by a cookie banner. We also use your browser's local storage to remember unfinished puzzles and your preferences — that stays on your device.

How long we keep it

For as long as you have an account. Delete your account and the associated data goes with it. Server logs kept by the services above expire on their own schedules, typically within a few weeks.

Your rights

You can delete your account yourself at any time: open your Profile and choose Delete account. It takes effect immediately and removes your progress with it. Feedback notes you sent us are kept, with nothing left that links them to you.

You can also ask for a copy of your data, ask for it to be corrected, or ask us to delete the account for you. Email hello@ascendoku.com and we will act within 30 days. You do not need to give a reason for a deletion request.

If you think we have handled your data badly, you can complain to the Finnish Data Protection Ombudsman at tietosuoja.fi.

Children

Ascendoku is suitable for all ages, but accounts are not intended for children under 13. If you believe a child has created one, email us and we will remove it.

Changes

If this policy changes in a way that matters, the date at the top changes and significant changes will be announced in the app.

Contact

Questions about any of this: hello@ascendoku.com.