Terms of Use
Last updated: 2 November 2026
The website
Color Contrast Check is a free, non-commercial website. It checks the contrast between two colors against the WCAG contrast criteria, simulates color vision deficiencies, and explains color contrast in a guide and examples. It needs no account and no payment, is offered as it is, and may change, pause or end at any time.
The website itself
The website's own code, design, texts and logo are mine. Don't copy, scrape, mirror or republish them without permission.
No guarantee of accessibility compliance
The contrast ratios and pass/fail results follow the WCAG 2 formula and are made with care, but come without guarantee. They are not an accessibility audit, legal advice or a certification. A passing result does not mean that a website, app, document or product meets WCAG, the European Accessibility Act (in Germany the BFSG), the ADA, or any other law or standard.
Contrast is only one part of accessibility. Check the results in context (font size and weight, how text renders, transparency, images behind text) and, where compliance matters, with an expert audit and testing with real people. The color blindness simulation shows how colors may look and is no substitute for testing with people who have a color vision deficiency.
Fair use
Don't misuse the website: no attacks, no probing for vulnerabilities or attempts to get around its security, no tampering with it, no reverse engineering of its code beyond what the law allows, no scraping or automated mass requests. Anyone who does will be blocked, and attacks may be reported.
Feedback
If you send ideas or feedback, I may use them to improve the website, without any obligation.
Liability
The website is free, so I am liable only for intent and gross negligence. Liability for injury to life, body or health and under mandatory law is not limited.
Links
Links to other websites are there for convenience; their owners are responsible for their content.
Law
German law applies. If you live in another country as a consumer, the mandatory consumer protection of that country still applies.
Privacy Policy
Last updated: 2 November 2026
In short
- Color Contrast Check is a free, non-commercial website. Nothing is sold, there are no ads and no accounts.
- Visits are counted with TelemetryDeck, a German analytics service, without cookies and without identifying you. You can turn it off.
- Contrast is calculated in your browser. The colors you check are never part of the usage stats.
- No data leaves the EU.
Who is responsible
Stefano Merlo
Berlin, Germany
Email: hello [at] colorcontrastcheck.com
Hosting and server logs
This website and its email are hosted by a provider based in the EU. With every request, such as opening a page, the server receives and logs your IP address, the date and time, the address requested, the referring page and your browser's user agent. The logs are deleted automatically after about a week. Legal basis: my legitimate interest in delivering the website and keeping it secure, Art. 6(1)(f) GDPR.
Usage stats
I count visits with TelemetryDeck (TelemetryDeck GmbH, Germany; servers in the EU), without cookies. Your browser sends each visit to this website's own server, which shortens your IP address and passes it on with your browser's user agent. TelemetryDeck uses them only to work out your country, browser, system and an anonymous visitor code that changes every day, so it can't recognise you across days, and stores neither. The site doesn't read device properties such as screen size or plugins.
A visit records the page with any campaign tags in its link (such as ref), your browser's language and, if you came from another site, its domain. It never includes the colors you check. TelemetryDeck keeps the counted visits, which aren't linked to you, as long as they're needed to see how the website is used. Legal basis: my legitimate interest in seeing how the website is used so I can improve it, Art. 6(1)(f) GDPR. You can object at any time with the switch under Your rights.
If you write to me, I use your message and address to reply and keep them as long as needed. Legal basis: my legitimate interest in answering you and fixing what you report, Art. 6(1)(f) GDPR.
Stored in your browser
Your choice if you turn off usage stats is saved in your browser's local storage. It is needed for the choice you make, so no consent is required (§ 25(2) TDDDG). It is never sent to me. Clear this site's data in your browser to delete it.
Colors you check
Contrast and simulations are calculated in your browser. A link you share contains the two colors in its address; when it's opened, they appear in the server logs like any other address requested.
Links to other websites
Nothing is sent to the sites this website links to until you click a link; from then on, their own privacy policies apply.
Providing data
You don't have to provide any data: the website works without writing to me, and you can turn off usage stats. Only the server logs are needed to deliver the pages.
Your rights
You have the right to access (Art. 15 GDPR), correct (Art. 16) or delete (Art. 17) your personal data, and to restrict its processing (Art. 18). Since the usage stats aren't linked to you as a person, I usually can't tell which records are yours. To use your rights, email me at the address above. You can also complain to a data protection authority (Art. 77), for example the Berliner Beauftragte für Datenschutz und Informationsfreiheit.
Right to object: you can object at any time to processing based on my legitimate interest (Art. 21 GDPR). For usage stats, use the switch below: this browser then sends nothing. Your choice is saved in your browser's local storage, so clearing this site's data clears it too. For anything else, email me.
Usage stats in this browser:
Changes
I update this page when the website changes how it handles data. The date at the top shows the latest version.