What formula is used for grayscale conversion?

The tool uses the ITU-R BT.601 luminance formula: gray = 0.299×R + 0.587×G + 0.114×B. This weights channels according to human perception, producing more natural-looking results than a simple average.

Is the alpha channel preserved?

Yes. Only the R, G, and B channels are modified. The alpha channel (transparency) is left unchanged, so any transparent areas remain transparent in the output PNG.

Can I convert PNG, JPEG, and WebP images?

Yes. Any image format your browser can display as an element can be processed — including PNG, JPEG, WebP, GIF, and BMP.

Image Grayscale

Convert any image to grayscale using pixel-level luminance calculation in the browser.

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FAQ

What formula is used for grayscale conversion?: The tool uses the ITU-R BT.601 luminance formula: gray = 0.299×R + 0.587×G + 0.114×B. This weights channels according to human perception, producing more natural-looking results than a simple average.
Is the alpha channel preserved?: Yes. Only the R, G, and B channels are modified. The alpha channel (transparency) is left unchanged, so any transparent areas remain transparent in the output PNG.
Can I convert PNG, JPEG, and WebP images?: Yes. Any image format your browser can display as an <img> element can be processed — including PNG, JPEG, WebP, GIF, and BMP.

The Image Grayscale converter uploads an image, reads every pixel via Canvas getImageData, and applies the standard luminance formula (gray = 0.299R + 0.587G + 0.114B) to produce a true perceptual grayscale. The result is written back via putImageData and exported as a PNG. All processing is fully client-side.