Help & FAQ
Getting Started
ScreenCheck Pro is a comprehensive suite of browser-based tools for testing and calibrating your monitor or display. All tests run entirely in your browser with no data collection or account required. Your test history is stored locally on your device for your convenience.
Simply select a test from the homepage, follow the on-screen instructions, and use keyboard shortcuts or touch gestures to navigate through each test.
Available Tests
Dead Pixel Detector
Test for dead or stuck pixels using full-screen solid colors. Navigate colors with arrow keys or swipes, click to mark suspected pixels. Best performed in a dark room with clean screen.
Refresh Rate Test
Verify your monitor is running at the correct Hz (60Hz, 144Hz, 240Hz). The test measures actual frame rate over 9 seconds using requestAnimationFrame for accuracy.
FPS Comparison Tool
See the visual difference between various frame rates (30/60/120/144/240 FPS). Compare side-by-side to understand the smoothness improvements of higher refresh rates.
Screen Resolution Detector
Detect resolution, pixel density (DPR), aspect ratio, color depth, and orientation. Includes multi-monitor detection and device classification.
Monitor Calibration Suite
Calibrate brightness, contrast, gamma (2.2), and color accuracy using test patterns. Adjust your monitor settings until patterns display correctly.
Input Lag & Latency Test
Measure display latency for gaming by timing click-to-visual responses across 5 rounds. Lower latency means better responsiveness for competitive gaming.
Backlight Bleed Checker
Check for backlight bleed and IPS glow using fullscreen black and gray levels. Test in a completely dark room with brightness at 100% for best results.
⌨️ Keyboard Shortcuts
Dead Pixel Detector & Backlight Bleed
| Arrow Right / Down | Next color/level |
| Arrow Left / Up | Previous color/level |
| Spacebar | Next color/level |
| Escape | Exit fullscreen |
| Click / Tap | Mark pixel (Dead Pixel only) |
General Navigation
| F11 | Toggle fullscreen (browser dependent) |
| Escape | Exit test / Close dialogs |
| Tab | Navigate between interactive elements |
Touch Gestures (Mobile/Tablet)
| Swipe Left/Right | Navigate colors/levels |
| Swipe Up/Down | Navigate colors/levels |
| Tap | Mark pixels / Select options |
🔧 Troubleshooting
Refresh Rate Test Shows Wrong Hz
- • Check OS settings: Windows: Settings → Display → Advanced → Refresh Rate
- • Browser limitations: Some browsers cap at 60Hz even if your monitor supports higher
- • Multiple monitors: Drag browser window to the correct monitor before testing
- • Background tabs: Close other tabs; browsers may throttle inactive windows
- • Power settings: Disable battery saver mode on laptops
Dead Pixel Test Not Fullscreen
- • Browser security: Click "Allow" when prompted for fullscreen permission
- • Manual fullscreen: Press F11 (Windows/Linux) or Ctrl+Cmd+F (Mac) to enter fullscreen
- • Mobile devices: Rotate to landscape and hide address bar by scrolling
Input Lag Test Shows High Latency
- • Human reaction time: This test includes your reaction time (~150-250ms average)
- • Wireless devices: Use wired mouse/trackpad for more accurate results
- • V-Sync: Disable V-Sync in browser if possible (limited browser control)
- • Background processes: Close other applications to reduce system load
- • Monitor settings: Enable "Game Mode" or fastest response time setting
Tests Not Working on Mobile
- • Limited accuracy: Mobile screens have different characteristics than monitors
- • Refresh rate: Most mobile devices are locked to 60Hz (some newer phones support 90Hz/120Hz)
- • Touch controls: Swipe gestures work on most fullscreen tests
- • Browser compatibility: Use Chrome or Safari for best results
History/Results Not Saving
- • Private/Incognito mode: History is cleared when you close the browser
- • Browser settings: Check if cookies/localStorage are enabled
- • Storage quota: Clear browser data if storage is full
- • Multiple devices: History is device-specific and doesn't sync
❓ Frequently Asked Questions
Is ScreenCheck Pro really free?
Yes! All tests are completely free with no premium tiers, subscriptions, or hidden costs. The site is supported through non-intrusive partner links.
Do I need to create an account?
No account needed! All tests run in your browser and results are stored locally on your device.
How accurate are these tests?
Browser-based tests are generally accurate but have limitations compared to professional hardware tools. Results are suitable for consumer displays and general diagnostics. For critical calibration, consider professional hardware colorimeters.
Can I use these tests for warranty claims?
These tests are for reference only. Manufacturers typically have their own dead pixel policies and testing requirements. Check your warranty terms before making claims.
Why do results vary between browsers?
Different browsers have different rendering engines, refresh rate handling, and performance characteristics. For most accurate results, use Chrome or Edge (Chromium-based browsers).
Can I test external monitors on a laptop?
Yes! Drag the browser window to your external monitor before running tests. Make sure the external monitor is set as the primary display or that refresh rate is configured correctly in OS settings.
What's the difference between backlight bleed and IPS glow?
Backlight bleed is a defect where light leaks from edges/corners at all viewing angles. IPS glow is a characteristic of IPS panels that appears as whitish glow when viewed at angles - it's normal and expected.
How many dead pixels are acceptable?
This varies by manufacturer. ISO 13406-2 standards allow several "acceptable" dead pixels depending on class (Class I = 0 defects, Class II = up to 2 dead pixels). Check your specific warranty terms.
🔒 Privacy & Data
All tests run locally in your browser. We do not collect, store, or transmit any personal data or test results to our servers.
Test history is stored in your browser's localStorage and never leaves your device. You can clear this data at any time using the "Clear History" buttons or by clearing your browser data.
Share links encode test results in the URL itself - no data is stored on our servers when you share results.
For complete details, see our Privacy Policy.
🤝 Partner Tools
Extend your troubleshooting workflow with trusted partners that complement ScreenCheck Pro.
Check out QuickRef.dev — interactive developer reference and code playground in the browser.