Terms of Use
How to use these free browser tests and interpret their results.
Service and operator
ReactionCheck is maintained by Anil Gautam and provides browser-based reaction and peripheral tests without an account or fee. Questions can be sent to anilgautamwork@gmail.com.
Results and limitations
Results reflect the events your browser reports and the conditions of your test. They are for personal comparison and troubleshooting, not medical assessment, professional certification, a hardware diagnosis or a guarantee of repair. Verify important findings using manufacturer guidance and other suitable checks.
Browser and hardware support varies. Features may change or become unavailable. Read the instructions and warnings for each tool, especially before enabling flashing colours in the stuck-pixel experiment. Stop if a test causes discomfort; do not press on or open a display to repair it.
Acceptable use
Use the tools on devices you are permitted to test. Do not disrupt the service, attempt unauthorized access or present simulated results as verified hardware or medical findings.
Your information and results
You may copy and share your own results. Test inputs and scores stay on your device. Optional analytics and information you choose to email are described on the privacy page. Linking to a test is welcome; this does not grant permission to claim affiliation with ReactionCheck or reuse third-party material without its owner’s permission.
Questions and updates
Contact us if these terms or a tool’s limits are unclear. These terms do not remove rights that applicable law gives you. Last updated 27 September 2026.