How grayscale conversion works
Each pixel's red, green and blue values are combined into one brightness value. The natural option uses the ITU-R BT.709 luminance weights (21% red, 72% green, 7% blue), because our eyes are most sensitive to green. That's why it looks more like a real black-and-white photo than a simple average of the three channels.
Black & white (threshold) turns every pixel either pure black or pure white. It's useful for scanned documents, signatures, stencils and laser engraving. Move the threshold slider until the text is crisp. Sepia gives a warm, vintage brown tint.
Increase contrast for a dramatic look. The conversion runs on a canvas in your browser at full resolution, so nothing is uploaded. For more effects, try the image filter studio.
Frequently asked questions
How do I make a picture black and white?
Choose the image and pick Grayscale (natural), then download.
What is the best setting for scanned documents?
Black & white (threshold), with the slider adjusted until the text is clean.
✨ New: Remove the background from any image free – private, in your browser, transparent PNG.
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