Duplicate ID Visual Finder

Overview

Finds duplicate HTML IDs and visually highlights them on the current webpage.

# Duplicate ID Finder Duplicate ID Finder is a Chrome extension that scans the current web page for duplicate HTML `id` attributes. Every HTML `id` should be unique within a document. When duplicate IDs exist, they can lead to unexpected behavior in JavaScript, CSS selectors, accessibility relationships, anchor links, and automated tests. This extension provides a quick way to identify duplicate IDs while inspecting a page. ## Features * Scan the current page for duplicate HTML `id` values * Display each duplicate ID that is found * Run the scan directly from the browser with a single click * No account, setup, or configuration required ## How It Works 1. Open the web page you want to inspect. 2. Click the Duplicate ID Finder extension icon. 3. Run the scan. 4. Review any duplicate IDs detected on the page. The extension analyzes the HTML of the current page and reports any repeated `id` values so they can be reviewed and corrected. ## Why It Matters HTML specifications require `id` values to be unique. Duplicate IDs can affect: * JavaScript methods such as `document.getElementById()` * CSS ID selectors * Accessibility and ARIA relationships * Anchor links * DOM manipulation * Automated testing By identifying duplicate IDs early, the extension helps improve HTML quality and makes debugging markup issues easier. ## Privacy Duplicate ID Finder performs its analysis locally in your browser. It does not require an account or additional configuration to scan the current page. Developed by John Paul Mariano.

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Details

Version
1.1.0
Updated
July 19, 2026
Flag concern
Size
94.63KiB
Languages
English
Developer
Email
johnpaulpmariano@gmail.com
Non-trader
This developer has not identified itself as a trader. For consumers in the European Union, please note that consumer rights do not apply to contracts between you and this developer.

Privacy

Manage extensions and learn how they're being used in your organization

The developer has disclosed that it will not collect or use your data. To learn more, see the developer’s privacy policy.

This developer declares that your data is

Not being sold to third parties, outside of the approved use cases
Not being used or transferred for purposes that are unrelated to the item's core functionality
Not being used or transferred to determine creditworthiness or for lending purposes

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