Color tools

Relative luminance from RGB

Relative luminance from RGB: enter R, G, B and get an instant result in your browser. Free, private, no account.

Relative luminance from RGB applies 0.2126 * r + 0.7152 * g + 0.0722 * b to the values you enter (R, G, B). Use it for quick color estimates from your own numbers—not for regulated engineering, tax filing, or clinical decisions. Everything runs in your browser; nothing is uploaded to our servers.

How to use

  1. Open Relative luminance from RGB and read the field labels (R, G, B).
  2. Replace defaults with figures from your spreadsheet, lab sheet, or quote.
  3. Press Calculate and note the output before changing another input.
  4. Bookmark this page if you reuse the same calculation often.

FAQ

Which numbers belong in Relative luminance from RGB?

Only the on-page labels: R, G, B. The tool does not guess hidden assumptions.

How does Relative luminance from RGB compute its result?

It evaluates 0.2126 * r + 0.7152 * g + 0.0722 * b. If your source uses different symbols, map them to these fields first.

Can I paste the Relative luminance from RGB result into Excel or Sheets?

Yes—copy the number and keep your own documentation of inputs for audit trails.

Is Relative luminance from RGB a substitute for professional color software?

No. It is a lightweight browser helper for one relationship; use certified tools for compliance work.

Embed this calculator

Paste the snippet on your site or blog — the widget stays responsive inside the iframe.

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