from

The from attribute indicates the initial value of the attribute that will be modified during the animation. When used with the to attribute, the animation will change the modified attribute from the from value to the to value. When used with the by attribute, the animation will change the attribute relatively from the from value by the value specified in by.

Four elements are using this attribute: <animate>, <animateColor>, <animateMotion>, and <animateTransform>

<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg">
  <rect x="10" y="10" height="100">
    <animate attributeName="width" fill="freeze" from="100" to="150" dur="3s"/>
  </rect>
</svg>

The exact value type for this attribute depends on the value of the attribute that will be animated.

When a list of values is defined via the values attribute, the from attribute is ignored.