Tools / Color Converter / RGB → HEX

RGB to HEX Converter.

RGB to HEX is the reverse of reading a hex string: take each 0-255 channel, convert it to a two-digit base-16 number, and concatenate them behind a #. The only gotcha is zero-padding — a channel like 5 must become 05, not 5.

Enter a RGB color

HEX —

All formats

The RGB → HEX formula

hex = '#' + toHex(R) + toHex(G) + toHex(B) where toHex(n) = n.toString(16).padStart(2,'0').

Worked example

Convert rgb(154, 42, 42):

Red: 154 = 9A in hex
Green: 42 = 2A in hex
Blue: 42 = 2A in hex
Concatenate: #9A2A2A

JavaScript

const h = n => n.toString(16).padStart(2,"0");
const hex = "#" + h(154) + h(42) + h(42); // "#9a2a2a"

FAQ

Why pad to two digits?

Each channel must occupy exactly two hex digits. Without padding, rgb(5, 16, 255) would collapse to #510ff instead of #0510FF.

Upper or lower case?

Both are valid and identical to browsers. Designers often prefer uppercase for readability; it carries no semantic difference.

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Library

Colour references for your next project

Compare the original references behind this archive. Check the contents, edition and format before choosing a book.

Book links are Amazon Associates affiliate links. Your price is unchanged; a small commission supports the archive. As an Amazon Associate we earn from qualifying purchases.

Sanzo Wada

A Dictionary of Color Combinations

The 2010 Seigensha republication of the 1933 original. Japanese import.

Every combination in it is already browsable free here, hex values and all. Buy this one for the object rather than the data — Seigensha's matte plates and Japanese binding, or a citable copy of the 1933 original. If you want plates this archive doesn't have, Vol. 2 is the one.

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Sanzo Wada

A Dictionary of Color Combinations Vol. 2

Seigensha, 2020. Japanese import.

Wada's 1935–1938 follow-ups: 72 plates on the Japanese seasons and 165 drawn from early-century fashion, interior, and graphic design. Not in Vol. 1. Not in this archive. The book itself is a design object — Japanese binding, matte pages, zero captions.

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Torn between the two Wada dictionaries? Vol 1 vs Vol 2, compared plate by plate →