Privacy policy
Last updated: 3 October 2026
Numart turns a photo into a paint-by-numbers kit: a numbered sheet, a colour guide and a list of paints, as one PDF. This page explains what personal data that involves, why, and what you can ask us to do with it.
Who is responsible
Numart is run by a private individual. For anything about your data, write to privacy@numart.app.
What we collect
When you sign in with Google
Sign-in goes through our own sign-in service. We ask Google only to confirm who you are, so it shares an identifier of your Google account and nothing else: no name and no email address. That identifier is all we keep to recognise you next time.
Your account
- how many sheets you have made, your weekly free allowance and any credits on your account;
- a record of each credit added or used: its amount and time;
- your sheet settings: number of colours, detail level, page size and fit.
Your photos
A photo you upload is processed in memory to make your sheet and is not stored. To make it quicker to re-render the same photo with other settings, we keep a traced description of it (outlines, regions and palette, not the photo itself) for up to two hours. The PDF is sent straight to you; we do not keep a copy.
Server logs
Our web servers log each request: your IP address, the time, the page requested and your browser's user agent. We use these logs only to keep the service secure and working.
Why we use it
- To provide the service you ask for: signing you in, making sheets, counting your allowance and credits. This is necessary to perform our agreement with you.
- To keep the service secure and fix problems, using server logs. This is our legitimate interest.
We do not sell your data, show ads or use tracking tools. We count visits to the website with Umami, which runs on our own server, sets no cookies and keeps no IP addresses: it records only which pages are visited, the referring site and the browser and device type. Information received from Google is used only to sign you in and is not shared with anyone else or used for any other purpose.
Who else handles it
- Google, when you choose to sign in with Google.
- Hetzner Online GmbH, which hosts our servers and their encrypted backups in Germany.
Cookies and browser storage
We use no advertising or analytics cookies. The website sets two cookies that keep you signed in: numart_sid holds a random session identifier, and numart_login lives only for the few minutes a sign-in takes. They are strictly necessary, so they need no consent. Your sign-in tokens stay on our server, never in your browser. Your browser's local storage keeps your sheet settings, the light or dark theme and whether you have seen the cookie notice; nothing there leaves your device.
How long we keep it
- Your account, allowance, credits and settings: for as long as you use Numart, or until you ask us to delete them.
- Sign-in data: as long as your account exists. Backups of the sign-in service are kept for 14 days.
- Encrypted backups of the account database: nightly copies kept for up to six months, so data you have deleted can remain in them until the oldest copy expires.
- Photos and PDFs: not kept, as described above.
- Server logs: only as long as needed for security and troubleshooting.
Your rights
You can ask us for a copy of your data, to correct it, to delete your account and everything linked to it, or to stop using it. Write to privacy@numart.app; we will answer within 30 days. If you are in the European Union, you can also complain to your data protection authority.
Children
Numart is not meant for children under 16, and we do not knowingly collect their data.
Changes
If this policy changes, we will update this page and the date at the top.