Privacy

geulssi has no accounts and never asks for your email. The only personal detail you can give it is a first name, on My name in Korean — see Names you type.

Kept in your browser only

• Your stamps (which letters and blocks you have finished), your choice about sharing handwriting and the date your browser was last counted as a visit (or, on our own devices, a note never to count it) are saved in your own browser (localStorage). They never leave your device. Clearing your browser data removes them.

Handwriting you choose to share

Once you have three stamps (or when you press I wrote it correctly), we ask whether you want to share the lines you draw. Nothing is sent unless you choose Share my lines.

If you share, we receive one record for each try at a block, sent when you clear it, move to another block, watch it again or leave the page. The try you just made when you choose to share is sent too. Each record holds:

• the block you were writing and the lines you drew in the box (as coordinates);
• the checker's result: whether it accepted the block, how many strokes you drew, which strokes did not match or were out of place, and whether any were written in another order or direction;
• whether you pressed I wrote it correctly;
• the width of your browser window, your screen's pixel density and whether you used a finger, pen or mouse;
• a random code, made in your browser and saved there when you first share, so we can tell that several blocks came from the same writer — it is not linked to you;
• the time we received it and the version of geulssi you used.

We do not store your IP address, name, email or anything that identifies you. We use these lines only to test and improve how geulssi checks handwriting. They are stored with our hosting provider, Cloudflare.

To stop sharing, clear this site's data in your browser (this also removes your stamps). You will be asked again, and you can choose No thanks.

Names you type

On My name in Korean your name is turned into Korean in your browser. If a name is not in our hand-checked list, or its stroke order is not ready yet, we store that name, how many times it was asked and the dates it was first and last asked — no IP address or other identifier — so we know which names to work on next. The part of the page address after # (where the name goes when you share a link) is never sent to our server. Two exceptions: a name that is in neither our list nor our pronunciation dictionary is sent to our server once, to estimate how it sounds (it is not written to our records); and a stamp card is made in your browser as soon as you finish the last block, so it is ready to share; making it loads its typeface from Google Fonts, which receives the letters on it (your name in Korean among them). The Korean letter shapes on our pages come from our own server.

Stamp cards and practice counts

When you open, share or download a stamp card or your stamp board picture, or copy its link, we add one to a daily count of each. We also count, per day, how many pages are opened, how many browsers open a page that day (your browser keeps the date it was last counted, so it is counted once a day; when an app's built-in browser hands a page to your phone's browser, the link carries that date so you are not counted twice), how many times someone starts writing on a page, gets their first stamp, earns a letter's stamp and prints a worksheet. These are totals only — no name, no IP address or other identifier. Your stamps themselves are kept only in your browser, and the pictures are made in your browser and stay on your device.

Visit statistics

We count visits with Cloudflare Web Analytics to see which pages are used and how fast they load. It records the page, the site that linked to it, your country, browser, operating system and device type (phone, tablet or computer). Cloudflare states that it does not use cookies or localStorage for this and does not fingerprint visitors by IP address or browser.

Other services

• Pages are served by Cloudflare, which receives your IP address with every request, as any web host does.
• Our pages and stamps use fonts from our own server. Only a stamp card loads its receipt typeface from Google Fonts, which then receives your IP address and the letters on the card (see above).
• There are no ads.