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Grayscale Converter

Convert color photos to black and white, or partially desaturate — no upload.

Choose an imageProcessed in your browser — no upload

Examples

Full black and white

Input

Colour portrait JPEG

Output

Classic black-and-white photo at intensity 100%

Muted colour

Input

Vibrant landscape PNG

Output

Desaturated, faded look at intensity 60%

About this tool

This free online grayscale image converter turns colour photos into black and white in your browser — nothing is uploaded. Drag the Intensity slider to control how much desaturation to apply: 100% for a full monochrome result, or lower values for a muted, partially desaturated look. The output preserves your original format and shows the file size so you can download with confidence.

How to use

  1. Drop a JPG, PNG, or WebP image into the upload zone.
  2. Adjust the Intensity slider (0–100%) — 100% is fully black and white.
  3. Click Apply to process the image.
  4. Preview the result and check the output file size.
  5. Click Download to save your grayscale image.

Frequently asked questions

How do I convert a photo to black and white online?

Drop your image into this tool, set the intensity to 100%, and click Apply. The grayscale conversion runs in your browser — no upload, free, instant.

Is the grayscale converter free to use?

Yes — completely free with no sign-up. Your image is processed locally in your browser and never uploaded anywhere.

What does the intensity slider do?

At 100% the image is fully black and white. Lower values blend the grayscale version with the original colour, letting you create a muted or desaturated look rather than a full monochrome.

Which image formats are supported?

JPG, PNG, and WebP. The output keeps the same format as the input — JPEG for JPG files, PNG for everything else.

Will the black-and-white image look different from what my phone produces?

This tool uses the standard luminance weights (the same ones used by browsers and CSS), which produce natural-looking results. Some phone apps apply extra tone curves or grain for a film look.

Can I use this to desaturate a colour image partially?

Yes. Lower the Intensity slider below 100% to blend the grayscale result with the original colour. At 50% you get a half-desaturated, muted look.

Does converting to grayscale reduce the file size?

Often yes, because monochrome images compress more efficiently. The output file size is shown after processing.

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