PRIVACY
Privacy Policy, your data stays in the browser.
This page explains what Tushuo Lab (tushuoit.com/xx) does and does not collect. One rule above all: every tool runs locally in your browser, so the text, images, PDFs and media you work with are never uploaded to our servers.
The short version
We only do two things: use anonymous traffic statistics to learn which tools are popular, and store your preferences (language, theme) locally in your own browser. Anything you process stays on your device.
What we collect
- Local processing, no upload: image compression, PDF, QR codes, hashing, OCR and video transcoding all run inside the browser. Your files are never uploaded.
- Anonymous analytics (Baidu Tongji): page path, referrer, device type, browser and OS, screen resolution, approximate region and visit time. Used to understand which tools matter, never to identify you.
- Local storage (localStorage): language preference, dark/light theme, remembered form inputs, calculation history and daily-game progress. Stored only in your browser — we cannot read it, and clearing site data removes it.
- Where input memory stops: calculation pages (mortgage, income tax, BMI, unit conversion and similar) remember the parameters you entered last time so you can pick up where you left off; the page says "Restored your last input" and offers a Clear button. Pages whose inputs may contain passwords, keys, tokens or ID numbers save nothing at all, and such fields are never remembered anywhere else either.
- Information you send us: if you email us, we see your address and the message content, used only to reply.
- Server access logs: to debug faults and prevent abuse, the server records visit time, IP, request path and status code, normally deleted automatically after 7-30 days and never used for marketing or profiling.
Cookies and third-party ads
- This site currently shows no third-party advertising and sets no advertising cookies.
- We may later join an ad network (Google AdSense, Baidu Union) to keep the service free. If that happens, the ad provider may use cookies or device identifiers to serve ads. You can refuse or delete cookies in your browser settings, and Google users can turn off personalised ads in Google Ad Settings.
- Third-party ad and analytics providers have their own privacy policies; their data processing is not controlled by this site.
What we never do
- No registration, and no collection of sensitive data such as phone numbers or ID numbers (tools like the ID checker compute entirely on your device).
- We never sell or trade your data.
- We never analyse your tool inputs on a server.
Children’s privacy
Our tools can be used by students for practice (mental arithmetic, olympiad problems, stroke-order animations), but we do not knowingly collect personal information from children under 13, and we never ask children to submit personal details.
Data security and deletion
Because we do not store what you type, there is nothing to delete in the cloud. Clear this site’s data in your browser settings and your preferences and history are gone, with no loss of functionality.
How long we keep data
We keep nothing you type, because it never leaves your device. Anonymous traffic statistics are retained by the analytics provider under its own policy, and server access logs are usually cleared after 7-30 days. Local data such as language, theme and history stays in your browser until you clear it.
Your rights
You can clear this site’s local data at any time, refuse or delete cookies in your browser, and turn off personalised ads in your ad settings. If applicable law (such as GDPR or CCPA) gives you rights to access, correct, delete or object to processing, tell us through the contact page: we answer within a reasonable period and never restrict tool access because you exercised a right.
Third-party links
Pages may link to other sites (open-source project homepages, references, official documentation). Those sites have their own privacy practices that we do not control; once you leave, please read their privacy policy.
Policy updates
This policy is updated as features and regulations change; the "last updated" date at the bottom always reflects the latest revision, and significant changes are announced on the site. Questions are welcome through our contact page.
Last updated：2026-09-24
FAQ
Do you upload my files?
No. Compression, conversion, PDF editing, OCR and video transcoding all run inside your browser. You can even disconnect the network after the page has loaded and keep working.
How do I delete the data stored on my device?
Clear this site’s data in your browser settings (cookies and site data). That removes the language, theme, remembered inputs, history and game progress, without affecting any tool.