Creating repeating patterns with SVG

Using <pattern> to define a repeating SVG pattern.

specify the pattern’s width and height properties
use that pattern to fill a <rect> shape that fills the SVG

Examples

Squiggle

<svg aria-hidden="true" width="100%" height="8" fill="none" xmlns="http://www.w3.org/2000/svg">
  <pattern id="a" width="91" height="8" patternUnits="userSpaceOnUse">
    <path d="M114 4c-5.067 4.667-10.133 4.667-15.2 0S88.667-.667 83.6 4 73.467 8.667 68.4 4 58.267-.667 53.2 4 43.067 8.667 38 4 27.867-.667 22.8 4 12.667 8.667 7.6 4-2.533-.667-7.6 4s-10.133 4.667-15.2 0S-32.933-.667-38 4s-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0" stroke="#000000" stroke-linecap="square"></path>
  </pattern>
  <rect width="100%" height="100%" fill="url(#a)"></rect>
</svg>

<svg aria-hidden="true" width="100%" height="8" fill="none" xmlns="http://www.w3.org/2000/svg">
  <pattern id="a" width="91" height="8" patternUnits="userSpaceOnUse">
    <path d="M114 4c-5.067 4.667-10.133 4.667-15.2 0S88.667-.667 83.6 4 73.467 8.667 68.4 4 58.267-.667 53.2 4 43.067 8.667 38 4 27.867-.667 22.8 4 12.667 8.667 7.6 4-2.533-.667-7.6 4s-10.133 4.667-15.2 0S-32.933-.667-38 4s-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0-10.133-4.667-15.2 0-10.133 4.667-15.2 0" stroke="#000000" stroke-linecap="square"></path>
  </pattern>
  <rect width="100%" height="100%" fill="url(#a)"></rect>
</svg>

Taken from Google’s material guidelines.