:focus‑visible Tester - Online Keyboard‑Only Focus Ring
Compare :focus and :focus‑visible styling. See which one applies when using mouse vs. keyboard. Accessible focus management.
UD5 Toolkit
A virtual flashlight transforms your device's screen into a powerful light source. By displaying bright colors at maximum screen brightness, it can illuminate dark spaces, serve as an emergency signal, or create ambient mood lighting. Unlike a physical flashlight, you can customize the color, brightness, and even add strobe effects — all directly from your browser with no app installation required.
Select Strobe mode to make the light flash at a customizable frequency (1–20 Hz). This is useful for parties, visual effects, or signaling attention. The SOS mode automatically flashes the international Morse code distress signal (three short, three long, three short flashes) — an essential feature for emergency situations. The Party mode smoothly cycles through vibrant colors for a dynamic light show.
Absolutely! The Virtual Flashlight is fully responsive and optimized for mobile devices. On smartphones, the light panel adjusts to a comfortable size, and you can tap it to enter fullscreen mode — turning your entire phone screen into a bright, uniform light source. It's perfect as a bedside light, reading lamp, or emergency flashlight when you need it most.
Fullscreen mode maximizes the light output by expanding the colored panel to cover your entire screen, eliminating distractions from controls and UI elements. This significantly increases the illuminated area and perceived brightness. Press F on your keyboard, tap the light panel, or click the Fullscreen button to activate it. Press Esc or tap again to exit.
The tool offers 10 carefully selected preset colors including Pure White (ideal for general illumination), Warm White (softer, eye-friendly for reading), Yellow, Orange, Red (great for preserving night vision), Pink, Purple, Blue, Cyan, and Green. You can also use the custom color picker to choose any color imaginable — millions of possibilities at your fingertips.
The Keep Screen On button attempts to use the browser's Wake Lock API, which prevents your device screen from dimming or sleeping while the flashlight is active. This feature requires a secure HTTPS connection and is supported on most modern browsers (Chrome, Edge, Safari on iOS 16.4+). If unsupported, we recommend manually setting your device's auto-lock/screen timeout to a longer duration in system settings.
Yes, completely free! There are no hidden costs, subscriptions, or account requirements. The tool runs entirely in your browser, with no data collection or advertisements. It works online and can also function offline once the page is loaded, making it a reliable companion for camping, travel, or emergency preparedness.
Definitely. The SOS mode is specifically designed for emergency signaling, flashing the universally recognized distress pattern. Combined with fullscreen mode at maximum brightness, your phone becomes a highly visible beacon. The strobe mode can also serve as a warning or attention signal. We recommend keeping this page bookmarked for quick access in unexpected situations.
Compare :focus and :focus‑visible styling. See which one applies when using mouse vs. keyboard. Accessible focus management.
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