About ScreenTestPro

ScreenTestPro started in 2025 as a small set of pages I used to check monitors for friends and for my own setup. Most free test sites I found were either covered in pop-ups or showed a pattern without explaining what to look for. I wanted tools that open straight into the test and then tell you, in plain language, whether what you see is normal.

What we focus on

• Test first. Every tool page opens directly into the test. Explanations come below it, not before it.
• Native-resolution patterns. Test patterns are drawn by your browser in real time instead of shown as compressed images, so compression and scaling can't hide or create defects.
• Honest limits. If a browser can't measure something accurately, such as true display input lag or GtG response time, the page says so and shows a better method.
• Privacy. Tests run on your device. Results are not uploaded.

How pages are reviewed

Each tool page is checked on real screens before it is published or updated: desktop monitors, a laptop panel and phones, in Chrome, Safari, Firefox and Edge. The guidance on each page, for example how to tell backlight bleed from IPS glow, comes from those checks and from common manufacturer warranty policies.

Funding

The tools are free and are paid for by a small number of Google AdSense ads. Ads are never shown on top of a running fullscreen test.

Contact

Found a bug, a browser where a test misbehaves, or a monitor problem we don't cover? Email hello@screentestpro.com.