files/en-us/web/api/abstractrange/startoffset/index.md
{{APIRef("DOM")}}
The read-only startOffset property of the {{domxref("AbstractRange")}} interface returns the offset into the start node of the range's start position.
To change the start position, use the {{domxref("Range.setStart()")}} method or a similar one.
An integer value indicating the number of characters into the {{domxref("Node")}} indicated by {{domxref("AbstractRange.startContainer", "startContainer")}} at which the first character of the range is located.
If the startContainer is a {{domxref("Node")}} of type {{domxref("Text")}}, {{domxref("Comment")}}, or {{domxref("CDATASection")}}, then the offset is the number of characters from the start of the startContainer to the boundary point of the range. For other {{domxref("Node")}} types, the startOffset is the number of child nodes between the start of the startContainer and the boundary point of the range.
const range = document.createRange();
range.setStart(startNode, startOffset);
range.setEnd(endNode, endOffset);
const startRangeOffset = range.startOffset;
{{Specifications}}
{{Compat}}