# HTML Validator Plus

> Use an online HTML checker to check your HTML code. Use a syntax checker as an HTML error checker

Canonical page: [https://chrome-stats.com/d/html-validator-plus](https://chrome-stats.com/d/html-validator-plus)

## Overview

- **ID:** `html-validator-plus`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** OK365
- **Category:** web-development
- **Daily users:** 14
- **Version:** 1.0.0.5
- **Last updated:** 2025-02-12
- **First published:** 2025-02-11
- **Size:** 2.73 MB
- **Data as of:** 2026-09-06
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/html-validator-plus/)

## Description

🧩 This Firefox extension offers a comprehensive set of features designed as an HTML checker to identify HTML error checks in the code. With a user-friendly interface, it allows you to perform HTML validation right from your browser, simplifying your workflow and improving productivity.

❗ With the extension you can:

1️⃣ to perform real-time;

2️⃣ to scan;

3️⃣ check for W3C compliance;

4️⃣ check for HTML errors;

5️⃣ fix markup errors;

6️⃣ to optimize each page.

🔑 Convenient Features:

➤ H TML Syntax Checker: The tool highlights syntax errors and suggests fixes, making it easier to write error-free code. It supports both new and older standards, ensuring comprehensive coverage.

➤ Error Explanations and Guidance: The HTML Validator provides detailed explanations and potential fixes for each detected error, serving as a valuable educational tool for both novice and experienced developers.

➤ Customizable Features: Adjust the Hypertext Markup Language validation rules to fit the specific requirements of your project, creating a flexible HTML validation environment. Options include ignoring certain rules or setting unique validation parameters for a custom method.

➤ Focus on user experience: With a clean and intuitive design, the HTML debugger ensures that HTML checking is a seamless part of your development process. It integrates seamlessly into your development environment, providing tooltips and context menus for easy access to its features.

🔑 Key features:
<ol><li>Extensive HTML checker reviews alert you to errors, outdated tags, and additional issues.</li><li>Instant HTML code checker verification allows for quick editing.</li><li>Online HTML validation confirms your site's markup complies with W3C standards.</li><li>Online HTML validator is capable of working offline.</li><li>Online HTML validation is designed to process multiple files at once quickly and efficiently.</li><li>Validate your markup in real-time as you edit or edit your markup.</li></ol>

## Rankings

- #29,780 — Overall
- #60 — html
- #125 — error
- #239 — x data

## Permissions and access

### Permissions

- `storage`
- `activeTab`
- `clipboardWrite`
- `webNavigation`
- `scripting`

### Host permissions

- `<all_urls>`

### Content script matches

- `<all_urls>`

## Safety

- **Risk impact:** High risk impact
- **Risk likelihood:** Moderate risk likelihood

### Analysis details

- Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
- This extension has low user count. Unpopular extensions may not be stable or safe.

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

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Source: [Chrome-Stats](https://chrome-stats.com/d/html-validator-plus)