Free Online Grayscale Image Tool

A grayscale tool removes colour from a photo using a luminance-weighted formula so perceived brightness stays accurate.

Your data is processed entirely in your browser and never sent to any server.

Instant results 100% private No signup needed

Drop an image here, or click to choose

Processed locally — your image never leaves the browser.

How to Use This Tool

  1. Drop or choose the colour image you want to convert.
  2. Leave intensity at 100 percent for full grayscale.
  3. Lower the slider for a faded, partly desaturated look.
  4. Click Download PNG to save the result.

What Is a Grayscale Image?

Grayscale conversion maps each colour pixel to a single shade of gray. The naive method averages red, green, and blue equally, but that misjudges brightness because the human eye is far more sensitive to green than to blue. The Rec. 601 luminance formula — 0.299 red, 0.587 green, 0.114 blue — weights the channels to match perception, giving a more natural result.

This tool applies that formula per pixel via getImageData, then blends between the original colour and the gray value using an intensity slider. At 100 percent you get full grayscale; lower values produce a faded, partly desaturated look popular in vintage edits.

Grayscale keeps all 256 tonal levels, which is different from true black-and-white (only pure black and pure white). The conversion runs entirely in your browser and exports a clean PNG.

Frequently Asked Questions

What formula is used?
Each pixel maps to luminance using 0.299 red, 0.587 green and 0.114 blue, the Rec. 601 weighting, so brightness looks correct to the eye.
Can I get a partial effect?
Yes. The intensity slider blends between the original color and full grayscale for a desaturated look.
Is grayscale the same as black and white?
No. Grayscale keeps 256 shades of gray; true black-and-white is only pure black and pure white with no mid-tones.

Published by the WeGotEveryTool team. We build and test every tool in-house and update pages when the underlying spec, formula, or recommendation changes.

Reviewed: May 2026. Disclaimer: this tool is provided as-is for general informational use. For decisions with material consequences (medical, legal, financial, security) verify results against a qualified professional source.

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