Find and update H3 Paragraphs using Apps Script


In today’s digital age, the efficiency and automation of document formatting can significantly enhance productivity. Google Docs users, in particular, can benefit from Google Apps Script, a powerful tool designed to extend the functionality of Google Workspace, including Docs, Sheets, and Forms. In this blog post, we’ll delve into a specific use case: a script that automatically updates all H3 paragraphs in a Google Document.

Understanding the Script

The script in focus, updateH3Paragraphs, serves a simple yet effective purpose. It adjusts the formatting of all H3 (Heading 3) paragraphs in a Google Document. Specifically, it sets the font size to 14 and ensures the text is not bolded. Here’s how it works:

Step-by-Step Breakdown:

  1. Opening the Document: The script starts by opening a specific Google Document. This is done using DocumentApp.openById(DOCID), where DOCID should be replaced with the ID of your document.
  2. Accessing the Body: Once the document is open, the script retrieves the document’s body, which contains all the text and elements of the document.
  3. Iterating Over Paragraphs: The script then gets all paragraphs from the document body and iterates over them using a forEach loop.
  4. Checking Paragraph Headings: For each paragraph, the script checks if its heading type is HEADING3 (H3). This is crucial as our goal is to modify only those paragraphs.
  5. Updating Formatting: If a paragraph is an H3, the script changes its font size to 14 and ensures that the text is not bolded.

Practical Applications

This script can be particularly useful in standardizing document formats, especially for lengthy documents like reports, proposals, or manuals. By automating the formatting of H3 headings, users can ensure consistency throughout the document, improve readability, and save time that would otherwise be spent on manual formatting.

How to Implement the Script

To implement this script:

  1. Open your Google Document.
  2. Navigate to Extensions > Apps Script.
  3. Delete any existing code and paste the script provided above.
  4. Replace DOCID with the actual ID of your Google Document.
  5. Save and name your script.
  6. Close the Apps Script editor and return to your document.

You can run the script directly from the Apps Script editor or create a custom menu in your Google Document for easier access.


The updateH3Paragraphs script is a testament to the power and flexibility of Google Apps Script, showcasing how a simple script can streamline the formatting process in Google Docs. By integrating such scripts into your workflow, you can enhance productivity, ensure consistency, and focus more on the content rather than the formatting. Whether you’re a seasoned developer or a novice to scripting, the customization possibilities with Google Apps Script are vast and can cater to a wide range of needs.

function updateH3Paragraphs() {
  var doc = DocumentApp.openById(DOCID);
  var body = doc.getBody();
  var paragraphs = body.getParagraphs();

  paragraphs.forEach(function(paragraph) {
    // Check if the paragraph's heading is NORMAL
    if (paragraph.getHeading() === DocumentApp.ParagraphHeading.HEADING3) {
      // Update the font size to 14 and make sure it's not bold