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LED Test

The tool you need for an LED test is the in-browser screen test at https://freetoolonline.com/device-test-tools/lcd-test.html - it paints solid red, green, blue, black, white, and yellow edge-to-edge so a dead or stuck pixel stands out against the uniform field on any LCD, OLED, or LED panel. No install, no account; open the page and tap a color.

Editorial team · Last reviewed: 2026-06-29

Property	Value
Format	Online tool, no install
Speed	Browser-side; output in seconds
Privacy	Files stay on-device (no upload)
Implementing tool	https://freetoolonline.com/device-test-tools/lcd-test.html

The test itself is one tap per color. Click a color tile (red, green, blue, black, white, or yellow) and the browser paints the chosen color across the full viewport, with an optional Fullscreen toggle on screens 821 pixels wide and larger so the color lifts past the browser chrome and address bar. A stuck pixel near the edge of the panel stays visible at arm's length on a fullscreen field where a tab strip would otherwise hide it. The Reset button drops the overlay so consecutive colors can be swept quickly without a refresh, and the page handles LCD, OLED, and LED panels on phone, laptop, and desktop browsers because the per-pixel response test is panel-type-agnostic.

Last updated: Jul 6, 2026

Reviewed by the Free Tool Online editorial team · Tested in the current versions of Chrome, Firefox, Safari, and Edge before publishing. No account is needed to use any tool. Report a bug - we triage within 72 hours. · Last refreshed April 2026.

Why trust these tools

Ten-plus years of web tooling. The freetoolonline editorial team has shipped browser-based utilities since 2015. The goal has never changed: get you to a working output fast, without an install.
No install, no sign-up. Open a tool and get a working output in seconds - nothing to download and no account to create. Tools that need heavy processing run it on our service, so even a low-powered machine gets the job done.
Analytics stops at the page view. We measure which pages get visited, not what you type or upload inside a tool. There is nothing to sign in to and no profile is attached to your input.
Open-source core components. The processing engines underneath (libheif, libde265, pdf-lib, terser, clean-css, ffmpeg.wasm, and others) are public and audit-able. We link to each one in its tool page's footer.
Free, with or without ads. All tools are fully functional without sign-up. The Disable Ads button in the header is always available if you need a distraction-free run.

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