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javascript/snippets/hex-to-rgb.md

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+---
+title: Hex to RGB
+type: snippet
+tags: [string,math]
+cover: umbrellas
+dateModified: 2020-10-19T22:49:51+03:00
+---
+
+Converts a color code to an `rgb()` or `rgba()` string if alpha value is provided.
+
+- Use bitwise right-shift operator and mask bits with `&` (and) operator to convert a hexadecimal color code (with or without prefixed with `#`) to a string with the RGB values.
+- If it's 3-digit color code, first convert to 6-digit version.
+- If an alpha value is provided alongside 6-digit hex, give `rgba()` string in return.
+
+```js
+const hexToRGB = hex => {
+  let alpha = false,
+    h = hex.slice(hex.startsWith('#') ? 1 : 0);
+  if (h.length === 3) h = [...h].map(x => x + x).join('');
+  else if (h.length === 8) alpha = true;
+  h = parseInt(h, 16);
+  return (
+    'rgb' +
+    (alpha ? 'a' : '') +
+    '(' +
+    (h >>> (alpha ? 24 : 16)) +
+    ', ' +
+    ((h & (alpha ? 0x00ff0000 : 0x00ff00)) >>> (alpha ? 16 : 8)) +
+    ', ' +
+    ((h & (alpha ? 0x0000ff00 : 0x0000ff)) >>> (alpha ? 8 : 0)) +
+    (alpha ? `, ${h & 0x000000ff}` : '') +
+    ')'
+  );
+};
+```
+
+```js
+hexToRGB('#27ae60ff'); // 'rgba(39, 174, 96, 255)'
+hexToRGB('27ae60'); // 'rgb(39, 174, 96)'
+hexToRGB('#fff'); // 'rgb(255, 255, 255)'
+```