Privacy policy

This page explains what data WhenAtlas collects when you visit it, why, and the choices available to you. It covers the website (including its Chinese version) and the video scenario player.

Summary

• We do not ask for or store your name, email address or any account credentials — there are no accounts.
• Your view of the map (time, camera, layers) is state held in your browser only; it never travels to us.
• We do not run third-party analytics, no cookies are set directly by us, and images and audio files are served from object storage rather than from analytics-instrumented origins.
• Advertising is served by Google, which may use cookies to measure and personalise ads; you can control it at adssettings.google.com.

Who we are

WhenAtlas is an interactive history atlas published by the team behind this site (see the about page for who we are). Any policy question can be sent via the contact page.

What we do not collect

• We do not collect, log or store personal information such as your name, email address, postal address, or payment details.
• We do not require registration or any form of sign-in.
• We do not fingerprint visitors, run data-broker pixels or embed third-party analytics.

Data stored on your device only

• Interface language (English or Chinese) is stored in local browser state so the site can reopen in your language.
• View state — the current time, camera position or active layers you reach via a map link — exists in the browser session and in URLs you choose to share; our servers do not record who viewed them.

Server and CDN logs

The site is served through a CDN, which keeps short-term access logs (requested URL, timestamp, status code, IP address) as an operational necessity — every website with a CDN does. We do not run our own analytics on those logs and we do not build profiles of visitors. Security or abuse-related logs are retained no longer than necessary for that purpose.

Cookies and advertising

WhenAtlas itself sets no cookies. From time to time we display advertising through Google AdSense to keep the atlas free. Here is what that involves:

• Google and its partners may use cookies or device identifiers to serve and measure ads, and, where permitted, to personalise them based on your visits to this and other sites.
• You can opt out of personalised advertising in your Google Ads Settings (adssettings.google.com), or via third-party tools such as aboutads.info.
• Visitors in the European Economic Area, the United Kingdom and Switzerland may choose through consent signals presented by the ad platform, and Google's advertising rules additionally restrict personalised advertising.
• Under CalOPPA and comparable frameworks, browsers' global privacy controls ('Do Not Track'-style signals) are honoured where technically applicable.

If advertising settings change materially, we will update this page and note the date of revision below.

Third-party media and assets

Map tiles are served from OpenFreeMap's public tile service under its own terms, and historical media such as public-domain images on some pages may be served from Cloudflare R2 or Wikimedia Commons. Those services see standard request data (such as your IP address and requested URL) when fetching tiles or media for you. Their handling of that data is governed by their respective policies.

Children's privacy

WhenAtlas is intended for a general audience and does not knowingly collect personal information from anyone, including children under 13. Because we do not operate registration or user-submitted content, no such data exists for us to collect.

Your rights and choices

Because we hold no personal records about you, there is generally nothing for us to access, correct or delete. If you believe we have held information about you contrary to this policy, email us and we will investigate and correct it. To opt out of personalised advertising, use the Google Ads Settings link above.

Changes to this policy

We publish updates to this page at the same URL whenever our practices change, with the revision date shown below.

Last updated: 2026-09-30