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Free tools › Images

Grayscale image

Every colour to a true grey, at full resolution, in the format you started with.

More free conversions, where you upload. The Fylane extension does the same work inside any upload form, on its own free share every day.Add to Chrome

How to grayscale image

  1. Drop the image.
  2. Pick a format, or keep the original’s.
  3. Press Convert and download.

What happens to your file

Each pixel’s three channels become one luminance value, weighted the way the eye weighs colour (green counts most, blue least), so a red and a green of equal brightness come out the same grey rather than one going dark. The image keeps its size and its EXIF orientation is applied on the way.

A PNG with transparency keeps it; a JPG stays a JPG at high quality. Nothing is resized.

Questions

Is this the same as desaturating?

Close, but better: plain desaturation averages the channels and makes some colours muddier than they look. A luminance-weighted grey keeps the tones you see.

Can I get a sepia or a tint instead?

Not here — this page is a true grey. Adjust image changes brightness, contrast and saturation if you want to soften colour rather than remove it.

Do it once, not on every form

A form that wants a square JPEG under 240 KB says so on the page. The Fylane extension reads that, fits your photo to it, and puts it in the field — without you working out what 240 KB looks like.

And it keeps the result. The next application that asks for a résumé, a cover letter and a photo fills all three from one tap, each one refitted to what that site accepts.

Your files stay in the browser, encrypted, on your machine. Nothing is uploaded to keep them and nothing is sent anywhere to fill a form.

Filmed from the extension: a phone portrait against a form that takes only a square JPEG under 240 KB.

Add to Chrome — freeWhat it does

Do this in code

curl -X POST https://api.fylane.dev/v1/jobs \
  -H "Authorization: Bearer $FYLANE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "file_id": "<file id>",
    "operation": "image.adjust",
    "options": {
      "grayscale": true,
      "format": "same"
    }
  }'

The same operation, image.adjust — Tone: grayscale, brightness, contrast and saturation — each optional, each a multiplier with 1 as unchanged. Answers WebP unless `format` says otherwise. Upload first with the quickstart; every option is on the operations page. 500 free credits a month, then $5 per thousand.