Validify icon

Validify

by Patrick Verhaert · Developer Tools
Manifest V3 Free
View in Chrome Web Store Data as of 16 Oct 2026

Validate HTML of the current page against W3C standards. View results in DevTools console or in the Validify Panel

Users
90
+9 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
2
0 in 30 days
Store rank
#87K
#73K among extensions
Version
0.1.0
updated 11 Dec 2025

Users

monthly, 10 months
04692Dec 2025Jun 2026Oct 2026
Latest, 16 Oct 2026: 90 usersMove the mouse over the chart for any month

Ratings count

monthly, 10 months
012Dec 2025Jun 2026Oct 2026
Latest, 16 Oct 2026: 2 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About Validify

Validate your HTML with a single click. For developers who need to ensure their code is compliant and clean, Validify brings the power of the W3C Nu HTML Checker directly to your browser. Inspired by the classic "Validity" extension, this modern, lightweight tool provides a streamlined workflow for web developers and QA engineers to check for HTML issues on the fly—including on pages rendered by JavaScript frameworks. HOW IT WORKS: 1. Click the Validify icon in your toolbar. 2. The extension sends the current page's generated HTML to the W3C validator. 3. The icon badge updates instantly with the total number of errors. 4. Open the Chrome DevTools (F12) and select the "Console" panel or the "Validify W3C Validation" panel for a detailed, interactive report of all errors and warnings. KEY FEATURES: • Dedicated DevTools Panel: Get a clean, organized, and filterable view of all validation issues right inside a custom DevTools panel. • One-Click Validation: No complex setup. Just click and see the results. • Developer Console Integration: For those who prefer the classic view, errors and warnings are also logged cleanly to the Console using console.group. • Dynamic Content Aware: Validates the generated HTML of the page, so it works perfectly with modern JavaScript frameworks (like React, Vue, Angular) and dynamic content. • At-a-Glance Badge: The extension icon shows the error count in red, turning green when the page is 100% valid. • Lightweight & Fast: Built with vanilla JavaScript for minimal performance impact. No ads, no tracking, just a simple and powerful developer utility.

Growth

WindowUsersChangeRatingsRating
7 days0+0.0%00.00
30 days+9+11.1%00.00
6 months+33+57.9%00.00

Version history

2 versions recorded
0.1.011 Dec 2025
0.0.18 Dec 2025

Details

Category
Developer Tools
First seen
8 Dec 2025
Size
42 KB
Languages
en
Pricing
Free
Extension ID
mcodhpijcbmcbeaobimpfoinafinojde

Permissions and risk

Low riskimpact 1, likelihood 2
Permissions
activeTabscriptingstorage
Site access
https://validator.w3.org/*

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