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HTML Entity Escape Studio & XSS Sanitizer

Escape <, >, &, ", ' to Named, Decimal & Hex entities; scan dangerous XSS vectors & secure web inputs.

⇄ Switch to Unescape

Entity Encoding Standard:

Escape Double and Single Quotes (" and ') Escape Backticks (`) for template literals

100% Client-Side RAM: Your source code is never sent to external servers.

⚠️ Security Warning: Dangerous XSS Vectors Detected in Source Code:

🛡️ All detected vectors are 100% neutralized once escaped!

Original Chars

Raw input length

Escaped Chars

Sanitized string length

Entities Escaped

Special tokens neutralized

Expansion Ratio

Payload size overhead

💻 Raw HTML Code / Text Source: 0 chars

0 chars

The XSS Vulnerability Nightmare: When a Single Less-Than Symbol (<) Breaches Security

For over two decades in the OWASP Top 10 web security benchmark, Cross-Site Scripting (XSS) has remained one of the most persistent and devastating vulnerabilities. The exploit vector is deceptively simple: an attacker posts user input containing executable tags like <script> or image event attributes like onerror=alert(...). If your web application renders this input raw into the DOM without escaping, victim browsers parse it as executable script rather than harmless data, silently exfiltrating session tokens and authentication cookies.

Why is transforming "<" into "<" universally recognized by security architects as the foundational defense against DOM injections? When the browser HTML tokenizer encounters <, it treats it strictly as a visual character entity for text rendering rather than a syntactical tag delimiter. PhuDuy Tools HTML Entity Escape Studio provides high-performance encoding across Named, Decimal, and Hexadecimal standards, complete with an integrated live XSS vulnerability inspector that detects dangerous vectors in local memory before they reach production.

3-Step Guide to Escape HTML & Verify Security

Sanitize input payloads, neutralize malicious scripts, and inspect live browser output.

Input Raw HTML or Payloads

Paste your HTML, XML, SVG, or raw user-submitted string into the left editor workspace.

Select Standard & Review Lint

Choose Named Entities for web embedding, or Decimal/Hex for security audits. Review flagged XSS alerts.

Copy Sanitized Safe Output

Toggle to Sandbox tab to confirm text appearance, click Copy to embed safely inside <code><pre> tags or database fields.

The 5 Critical HTML Special Characters Reference Table

Standards for DOM boundary protection and Cross-Site Scripting mitigation.

Character	Entity Name	Named	Decimal	Hexadecimal	Security Risk if Unescaped
<	Less-than	<	<	<	Opens arbitrary executable HTML/script tags
>	Greater-than	>	>	>	Closes HTML elements prematurely and breaks DOM tree
&	Ampersand	&	&	&	Collides with existing entities and query strings
"	Double quote	"	"	"	Breaks out of HTML attribute boundaries to inject events
'	Single quote	'	'	'	Breaks inline JS string literals in attribute handlers

4 Market-Leading Features

Engineered to rigorous OWASP web application security standards.

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Integrated XSS Vector Security Linter

Automatically flags dangerous executable tags, inline DOM event handlers (onload, onerror), and javascript: URIs in real-time.

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Multi-Standard Encoders (Named, Dec, Hex)

Effortlessly switch between human-readable HTML5 Named entities, Decimal ASCII codepoints, or Hexadecimal for WAF security bypass audits.

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Live Dual-View Browser Sandbox

Directly preview both the raw escaped string and how client browsers render it safely as innocent visual text.

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Zero-Telemetry 100% Client-Side

Sensitive proprietary code and payloads are computed in local browser memory with zero network requests or database logging.

Frequently Asked Questions

Answers regarding web application sanitization, XSS mitigation, and entity standards.

Why is HTML escaping mandatory when displaying source code on websites? ▼

When publishing tutorials containing markup like "<div>Hello</div>", unescaped "<" and ">" characters cause browsers to interpret them as live DOM nodes, hiding the tags and breaking layout. Escaping to "<div>Hello</div>" forces the browser to render the literal code snippet intact.

What is the difference between Named (<) and Numeric (<) entities? ▼

Both render identically as "<". Named entities (<) use descriptive mnemonics ("less than") that are human-readable. Numeric entities (< decimal or < hex) represent direct Unicode/ASCII codepoints, providing universal compatibility across XML, SGML, and legacy email clients.

How do I unescape an escaped HTML string back to original code? ▼

You can use our complementary HTML Unescape tool by clicking "Switch to Unescape" in the top toolbar to instantly revert &lt;, &gt;, and &amp; back into raw <, >, and & tokens.

Does the tool corrupt or alter accented Vietnamese characters? ▼

Never. In standard modes, the tool preserves 100% of UTF-8 accented characters and exclusively targets the five critical structural delimiters (<, >, &, ", ') to ensure minimal payload overhead.

Is proprietary code or sensitive customer data uploaded to external servers? ▼

Guaranteed 100% local. All XSS pattern detection and string transformations execute solely inside your local browser memory sandbox. Zero data leaves your computer.

Ecosystem