What formula is used?

Common formula: Gray = 0.299×R + 0.587×G + 0.114×B (ITU-R BT.601). Alternative: (R+G+B)/3 or 0.2126×R + 0.7152×G + 0.0722×B (BT.709).

Do I need to upload an image?

No. You enter R, G, B values (0–255) and get the grayscale value. No image processing.

Human eyes are more sensitive to green, so green has a higher weight in the luminance formula.

Convert RGB values to grayscale using standard luminance formula (no image upload). Client-side only.

Method

R (0–255)

G (0–255)

B (0–255)

Result: Gray = 128 (128.00)

What formula is used?: Common formula: Gray = 0.299×R + 0.587×G + 0.114×B (ITU-R BT.601). Alternative: (R+G+B)/3 or 0.2126×R + 0.7152×G + 0.0722×B (BT.709).
Do I need to upload an image?: No. You enter R, G, B values (0–255) and get the grayscale value. No image processing.
Why different coefficients?: Human eyes are more sensitive to green, so green has a higher weight in the luminance formula.

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