What happens to pixels that don't match?

They're converted to grayscale using standard luminance weights and then dimmed to 40% of that brightness, which visually recedes them so the matching color pixels stand out clearly.

Does the highlighted color itself change?

No, matching pixels keep their exact original color and alpha untouched; only the non-matching pixels are altered.

How do I control how strict the match is?

The tolerance setting controls how far a pixel's color can be from your target and still count as a match, measured as Euclidean distance in RGB space. Lower values only catch near-exact matches; higher values catch a broader range of similar shades.

Why would I use this instead of the Color Extractor?

The Color Extractor tells you what a dominant color is; this tool shows you visually where a specific color you already know appears across the whole image, which is useful for spotting patterns or verifying coverage.

Color Pixels Highlighter - Spot Where a Color Appears in a PNG

Overview

Introduction

This tool visually highlights every pixel that matches a chosen color in a PNG, dimming everything else so matches stand out at a glance, entirely in your browser.

It's a fast way to answer 'where exactly does this color show up in my image?' without scanning pixel-by-pixel.

What Is Color Pixels Highlighter?

A client-side color-spotting tool that reads an uploaded PNG's pixel data, compares every pixel to a target color, and leaves matches at full brightness while converting non-matches to dim grayscale.

An adjustable tolerance controls how close a color needs to be to the target to count as a match.

How Color Pixels Highlighter Works

For every pixel, the tool measures the Euclidean distance between its RGB value and the target color. Matching pixels are left completely untouched; non-matching pixels are converted to grayscale using standard luminance weights and then dimmed to 40% brightness.

The contrast between full-color matches and dim gray non-matches makes matching regions immediately visible.

When To Use Color Pixels Highlighter

Use it to check exactly where a specific brand color appears across a complex graphic, verify that a highlight color is used consistently, or debug why a particular shade seems to be showing up in unexpected places.

It's also useful as a visual complement to the numeric Color Picker and Palette Extractor tools.

Often used alongside PNG Color Remover, PNG Colors Separator and PNG Color Picker.

Features

Advantages

Makes color distribution immediately visible rather than requiring pixel-by-pixel inspection.
Leaves matching pixels completely unaltered, so you see their true original color.
Runs entirely client-side; your image never leaves your device.

Limitations

It highlights one target color per run; comparing multiple colors requires multiple passes.
On images with many similar shades, a low tolerance may miss visually-similar pixels you'd consider a match.

Examples

Find every red UI element in a mockup

Input

A UI screenshot PNG, target #ff0000, tolerance 20

Output

The screenshot with red elements in full color and everything else dimmed to gray

A moderate tolerance catches slightly varied reds (like hover states) alongside the exact target shade.

Verify consistent use of a highlight color

Input

A design system export, target #ffcc00, tolerance 5

Output

Only near-exact matches of the highlight color remain in full color

A tight tolerance confirms whether the highlight color is used consistently or with unintended variation.

Best Practices & Notes

Best Practices

Start with a low tolerance to check for exact-match consistency, then raise it if you want to catch a broader family of similar shades.
Use the Color Picker tool first to grab an exact target hex value from the image itself.

Developer Notes

The highlight/dim logic is a pure function over a Uint8ClampedArray pixel buffer, reusing the shared clampByte helper for the luminance and dimming math, with no DOM dependency, so it's fully unit-testable.

Color Pixels Highlighter Use Cases

Auditing where a specific brand or highlight color appears across a complex graphic
Debugging unexpected color bleed or inconsistency in a design export
Visually verifying color-matching logic before automating it elsewhere

Common Mistakes

Setting tolerance too low and missing visually-similar shades you'd naturally consider a match.
Expecting multiple colors to be highlighted at once — this tool targets one color per run.

Tips

Pair with the Color Palette Extractor: extract the palette first, then highlight each top color one at a time to see its footprint.
If matches look too sparse, gradually raise the tolerance rather than jumping straight to a very high value.

Color Pixels Highlighter