Firefox Browser Add-ons
  • Extensions
  • Themes
    • for Firefox
    • Dictionaries & Language Packs
    • Other Browser Sites
    • Add-ons for Android
Log in
Preview of DOM Structure Mapper

DOM Structure Mapper by Levent B.

Visually highlights DOM parent/child nesting when hovering over elements on a webpage.

Available on Firefox for Androidโ„ขAvailable on Firefox for Androidโ„ข
0 (0 reviews)0 (0 reviews)
Download Firefox and get the extension
Download file

Extension Metadata

Screenshots
Settings pageShowcaseMore settings
About this extension
DOM Structure Visualizer - Instantly See the DOM Tree

Ever struggled to understand how elements are nested on a web page?
DOM Structure Visualizer makes it effortless. Simply hover over any element, and the extension instantly highlights its parent elements, direct children, and the element itself, all with distinct, color-coded outlines and informative labels.

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

โœจ KEY FEATURES

โ€ข ๐Ÿ–ฑ๏ธ Hover to Visualize โ€” Move your cursor over any element to instantly see its position in the DOM hierarchy. No clicking, no inspecting, no dev tools required.

โ€ข ๐ŸŽจ Color-Coded Highlights โ€” Hovered elements, parents, and children each get their own distinct color, making it easy to understand nesting at a glance.

โ€ข ๐Ÿท๏ธ Smart Labels โ€” Floating labels show each element's tag name, ID, classes, and dimensions. Toggle them on or off as needed.

โ€ข โฌ†๏ธโฌ‡๏ธ Parent & Child Control โ€” Choose whether to highlight parent elements, child elements, or both. Adjust parent depth from 1 to 5 levels.

โ€ข ๐ŸŽจ 4 Color Schemes โ€” Choose from Default, Neon, High Contrast, or fully Custom colors. The Custom theme lets you pick exact colors using HEX codes, RGB values, or a color picker.

โ€ข โš™๏ธ Full Settings Page โ€” Access advanced settings through the gear icon or your browser's extension options. Includes a live preview so you can see your color choices in real time.

โ€ข ๐ŸŒ 50+ Languages โ€” Fully localized interface supporting over 50 languages including English, Spanish, French, German, Japanese, Chinese, Arabic, Hindi, and many more.

โ€ข โšก Performance-First โ€” Uses requestAnimationFrame, event throttling, and minimal DOM manipulation. Designed to run smoothly even on complex pages.

โ€ข ๐Ÿ”’ 100% Private โ€” Zero data collection. No analytics, no tracking, no network requests. Everything runs locally in your browser. Verify it yourself โ€” the source code is fully open.

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

๐ŸŽฏ PERFECT FOR

โ€ข Web developers debugging layout and structure issues
โ€ข Students learning HTML and CSS
โ€ข Designers inspecting how pages are built
โ€ข QA testers verifying DOM structure
โ€ข Anyone curious about how websites are constructed

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

๐Ÿ›ก๏ธ PRIVACY & TRUST

DOM Structure Visualizer is completely open source under the MIT License. It requests only the minimum permissions needed (activeTab and storage). It makes zero network requests โ€” ever. Your browsing data never leaves your device.

Read our full privacy policy: https://e8013585.github.io/dom-structure-visualizer-privacy-policy/

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

๐Ÿ“– HOW TO USE
  1. Click the extension icon in your toolbar
  2. Toggle the visualizer ON
  3. Hover over any element on the page
  4. See the DOM hierarchy highlighted instantly
  5. Adjust settings to your preference

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

๐Ÿ’ป OPEN SOURCE

This extension is free, open source, and community-driven. Contributions, bug reports, and feature requests are welcome on GitHub:
https://github.com/e8013585/dom-structure-visualizer

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

If you find DOM Structure Visualizer useful, please consider leaving a rating โญ โ€” it helps others discover the extension. Thank you!
Rated 0 by 0 reviewers
Sign in to rate this extension
There are no ratings yet

Star rating saved

5
0
4
0
3
0
2
0
1
0
No reviews yet
Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
  • Support Email
Version
1.0.0
Size
136.03 KB
Last updated
19 days ago (Apr 19, 2026)
Related Categories
  • Web Development
License
MIT License
Privacy Policy
Read the privacy policy for this add-on
Version History
  • See all versions
Add to collection
Report this add-on
Go to Mozillaโ€™s homepage

Add-ons

  • About
  • Firefox Add-ons Blog
  • Extension Workshop
  • Developer Hub
  • Developer Policies
  • Community Blog
  • Forum
  • Report a bug
  • Review Guide

Browsers

  • Desktop
  • Mobile
  • Enterprise

Products

  • Browsers
  • VPN
  • Relay
  • Monitor
  • Pocket
  • Bluesky (@firefox.com)
  • Instagram (Firefox)
  • YouTube (firefoxchannel)
  • Privacy
  • Cookies
  • Legal

Except where otherwise noted, content on this site is licensed under the Creative Commons Attribution Share-Alike License v3.0 or any later version. Android is a trademark of Google LLC.