Googie Tools

Free Colour Screen & Pixel Tester

Create fullscreen colour tests, inspect pixels, cycle display colours, and sample HEX, RGB, HSL, HSV, and CMYK values from your screen or images.How to use

Background colour

Choose a solid colour for your display test. All formats stay in sync.
Optionally add a cursor marker that follows your pointer.

Colour cycle

Cursor Marker

Pixel test workflows

Screen colour preview

Move over the preview to try the cursor marker on #000000.

Colour values

Image colour picker

Upload, paste, or load an image by URL, or pick a colour from your screen. Click a pixel (or use the eyedropper) to sample HEX, RGB, HSL, HSV, and approximate CMYK.

Load an image

Pick from your screen

Image preview

Sample a pixel or pick from your screen

Shortcut guide

Shortcuts work in fullscreen test mode. They stay off while you type in a field. Press F here to start the test, or ? during a test for help.

  • R G B W KMarker red, green, blue, white, black
  • C M YMarker cyan, magenta, yellow
  • [ ]Decrease / increase marker size
  • OToggle outline or filled marker
  • HHide or show the system cursor
  • SpaceNext background colour
  • PPause or resume auto-cycle
  • FStart fullscreen from setup
  • EscExit fullscreen test mode
  • Double-clickEnter from the preview, or exit fullscreen test mode
  • ?Show or hide shortcut help in test mode

Ready to inspect your display? Launch the fullscreen colour test when your settings look right.

Colour Screen & Pixel Tester workspace

How to use it

Three quick steps from colour choice to fullscreen inspection.

  1. Step 1

    Choose a colour

    Pick a preset, enter HEX/RGB/HSL/HSV/CMYK values, or sample a colour from your screen, an image or camera (if your device supports it).

  2. Step 2

    Set up your test

    Optionally enable the cursor marker and adjust its colour, size, and shape. Build a colour cycle from presets or colours you add yourself. Save the colour values as a PDF for future reference.

  3. Step 3

    Start fullscreen

    Launch the colour test with the button, or double-click the preview window. When you are done, press Esc, use Exit test, or double-click the screen to leave fullscreen.

Common use cases

Practical ways people use this free colour screen and pixel tester.

  • Find dead or stuck pixels

    Apply the RGB pixel-test workflow, cycle solid colours in fullscreen, and use the cursor marker to inspect suspicious spots.

  • Check display uniformity

    Use the uniformity or backlight workflows, then cycle white and greys to look for brightness shifts, backlight bleed, or uneven panels.

  • Create a quick chroma-key backdrop

    Fill the display with practical chroma green or blue for casual video and photo work.

  • Build and compare colour palettes

    Graphic designers can collect presets or custom colours into a cycle, flip through them on screen, and judge how a palette looks together before committing to a design.

  • Grab colour values for web and UI work

    Web designers can quickly copy HEX, RGB, HSL, HSV, and CMYK values to use in mockups, CSS, and design tools during the design process.

  • Colour-match from reference photos

    Sample colours from an uploaded image, pasted screenshot, camera photo, or anywhere on your screen to match real-world or brand reference colours.

  • Save palettes for later

    Export your colour list as a PDF with swatches and values so you can reuse the palette as a quick reference in future projects.

  • Inspect subpixels up close

    Use a black background with a coloured cursor marker to examine individual red, green, and blue subpixels more carefully.

  • Validate projectors and large screens

    Run fullscreen colour tests to verify projectors, TVs, and meeting-room displays.

  • Reference lighting and UI contrast

    Use solid colour fields as photography lighting references or quick UI spacing and contrast checks.

FAQ

Quick answers about privacy, CMYK, chroma key, and fullscreen exit.

Is the Colour Screen & Pixel Tester free?

Yes. You can run fullscreen colour tests, inspect pixels, cycle colours, and sample values without paying or creating an account.

100% FreeGoogie Tools

Are my images uploaded to a server?

No. Uploaded, pasted, and locally selected images stay in your browser for this tool. We do not upload them to our servers to sample colours. See our Privacy Policy for full details.

Does this fix dead pixels?

No. This tool helps you inspect displays with solid colours and a cursor marker. It does not repair hardware. Some stuck pixels recover on their own; others need manufacturer support.

Why are CMYK values approximate?

Screens use RGB light. CMYK is a print colour model. The values here are a mathematical approximation for convenience and may not match printed output or colour-managed workflows.

What if my browser does not support screen colour picking?

The EyeDropper API is not available in every browser. You can still upload, paste, or load an image and sample a pixel from the preview.

Why can’t I sample some image URLs?

Many websites block cross-origin pixel reads (CORS). If an image displays but cannot be sampled, download it and upload it here instead. Googie Tools cannot bypass that browser security rule.

Is chroma green the same as ordinary green?

No. Ordinary RGB green is pure #00FF00. Chroma green is a practical digital key colour chosen for keying workflows. There is no single universal professional standard.

How do I exit fullscreen test mode?

Press Esc, use the on-screen Exit test control, double-click the screen, or leave the browser’s fullscreen UI. You are never locked in without an exit path. Tip: double-click the preview window to start fullscreen as well.

Can rapid colour cycling cause discomfort?

Yes. Rapid colour changes may be uncomfortable for some people. Prefer slower intervals, use Manual when inspecting carefully, and respect your browser’s reduced-motion preference.

More questions? See the full FAQ page or Privacy Policy.

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