Convert RGB color to hex

Pack three 0–255 channels into a #rrggbb string.

JavaScript Version 1.0.0 · MIT · .md

function rgbToHex({ red, green, blue }) { return `#${((1 << 24) + (red << 16) + (green << 8) + blue).toString(16).slice(1)}`; }

Input & expected output

{
  "red": 28,
  "green": 97,
  "blue": 65
}

"#1c6141"

The edge case

{
  "red": 0,
  "green": 0,
  "blue": 0
}

"#000000"

Know the limits

• The 1 << 24 term keeps leading zeros. Channels must be integers from 0 to 255.

The function above is the implementation used by the lab. The lab validates JSON types and caps size before execution; include equivalent validation when accepting untrusted input in your application.

Keep exploring

• Convert Celsius to Fahrenheit — Apply the temperature conversion without rounding the result.
• Convert hex to RGB — Expand #rgb if needed and read the red, green and blue channels.
• Convert URL parameters to object — Read a query string into an object; repeated keys become arrays.