Why do R, G, and B use different weights?

The human eye is most sensitive to green light and least sensitive to blue, so green contributes the most (587) and blue the least (114) to perceived brightness, even at equal numeric values.

What brightness threshold indicates a 'light' color?

127.5 (half of 255) is a commonly used midpoint threshold — colors above it are usually paired with dark text, and colors below it with light text, for readable contrast.

Color Brightness Calculator

Calculate a color's perceived brightness using the standard weighted luminance formula, which accounts for the human eye's differing sensitivity to red, green, and blue light. Useful for deciding whether to use light or dark text on a colored background.

Inputs

Results

Perceived Brightness (0-255): 122
Is Light? (1 = yes, 0 = no): 0

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Formula

Brightness = (R × 299 + G × 587 + B × 114) / 1000

Learn How This Works

Color Temperature and Mood: From Kelvin to Pastel Palettes

How color temperature in Kelvin, mireds, perceived brightness, and pastel generation all shape the mood a color communicates.

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