Encode

HTML Encoder and Decoder

Paste plain text, a template fragment, an attribute value, or an entity string to encode and decode HTML entities in the browser. Encode mode can escape HTML-sensitive characters such as angle brackets, quotes, apostrophes, and ampersands, or use an extensive HTML5 entity mode for broader entity output. Decode mode restores named, decimal numeric, and hexadecimal numeric entities for rich text, crawler output, log fields, and double-encoding checks.

  • Encode angle brackets, quotes, apostrophes, and ampersands to reduce accidental tag or attribute parsing
  • Choose special-character escaping for everyday HTML safety, or extensive HTML5 entity output for broader compatibility
  • Decode named entities, decimal numeric entities, and hexadecimal numeric entities while leaving unknown entities unchanged
  • Useful for template text, attributes, rich text, email source, CMS content, crawler output, and log fields
  • Reuse output as input to check for double encoding, missing entities, or irreversible context handling
  • Run every conversion inside the current browser tab, without uploading pasted content
tools/HTML Encoder and Decoder
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Encode · Special characters
HTML entity commands

Overview

A local HTML entity workspace for deciding whether content should be displayed as text, whether it has already been entity-encoded, and what should happen before it enters attributes, email, CMS fields, or logs.

  1. 01

    Special-character encoding

    Convert angle brackets, double quotes, apostrophes, and ampersands into entities for code samples, user text, and product copy that need to appear inside HTML text nodes or attribute values.

  2. 02

    Extensive HTML5 entity encoding

    Use extensive HTML5 entity output when symbols, punctuation, mathematical characters, currency signs, and other supported characters need to be represented as entities for older systems, email source, or explicit entity-output requirements.

  3. 03

    Entity decoding

    Restore named entities, decimal numeric entities, and hexadecimal numeric entities into readable text so you can inspect the real content, encoding depth, and source-system output rule.

  4. 04

    Template output checks

    Quickly tell whether template output is unencoded, encoded once, or encoded more than once, before code samples, user text, or rich text summaries are parsed or displayed incorrectly.

  5. 05

    Attribute text handling

    Prepare text for title, alt, aria-label, and data attributes with special attention to quotes, apostrophes, ampersands, and angle brackets that can break attribute boundaries.

  6. 06

    Round-trip verification

    Send the output back to the input and switch mode to check whether content stays consistent, and to spot double entity encoding or HTML that was treated as plain text.

  7. 07

    Sample inputs

    Built-in HTML snippet, attribute text, and entity text samples help confirm the current mode before you paste real content.

  8. 08

    Local-only processing

    Conversion, copy, and round-trip checks all happen in the browser. Template drafts, email source, internal logs, and CMS content stay on the device.

How to use

Choose a conversion direction, paste input, choose an encoding mode when needed, and the output updates live.

  1. 01

    Choose Encode or Decode in the conversion mode control.

  2. 02

    Paste text, an HTML snippet, or an entity string into the input area.

  3. 03

    When encoding, use special-character mode for HTML-sensitive structure characters, or extensive HTML5 entity mode for broader entity output.

  4. 04

    Inspect the output and confirm whether it will be used in a text node, an attribute value, or documentation.

  5. 05

    Copy the result, or use the output as input and switch mode to verify it returns to the original text.

Details

HTML entity conversion is less about converting more characters and more about knowing whether content is entering a text node, an attribute, email source, or another format boundary.

  • Use Encode with special-character mode when page body content needs to show code samples, angle-bracket text, or user-provided text.
  • For attribute values, focus on quotes, apostrophes, ampersands, and angle brackets. If the attribute is a URL, apply URL encoding rules too.
  • Use Decode when inspecting entity text from email source, CMS fields, crawler output, or logs before cleanup.
  • Use extensive HTML5 entity mode when you need broader named or numeric entity output for older systems, email source, or explicit entity-output requirements.
  • If content later enters JSON, a JavaScript string, or CSS, apply the correct encoding at that boundary instead of treating HTML entities as universal escaping.
  • When some HTML tags are allowed, use an HTML sanitizer with an allowlist. Entity encoding changes character representation; it does not filter tags or attributes.

Use cases

HTML entities appear in templates, rich text, email, crawler output, CMS fields, and log inspection. This tool is meant for small text conversions you can inspect and copy.

  1. Displaying code samples

    Encode a tag or UI example before placing it in documentation body text, so the browser displays it as text instead of parsing it as real HTML.

  2. Preparing attribute values

    Before putting text into title, alt, aria-label, or data attributes, encode quotes and ampersands to reduce the risk of breaking the attribute structure.

  3. Checking template output

    Compare text before and after rendering to see whether it is unencoded, encoded once, or encoded more than once.

  4. Inspecting rich text content

    Take entity text from an editor, CMS, or database field and decode it to see what the user actually entered.

  5. Reading email source

    HTML email and email templates often contain entities. Decode them to inspect headings, button copy, and legal text faster.

  6. Cleaning crawler output and logs

    Restore entities from scraped content, error logs, or API responses so the text is easier to read and clean up.

  7. Handling symbols and legacy pipelines

    Use extensive HTML5 entity mode when special symbols, punctuation, mathematical characters, or legacy output requirements need entity-style representation.

  8. Checking an encoding strategy

    Before changing a template engine, escaping function, or CMS output rule, validate a small sample against the expected entity conversion.

See also

If entity-encoded text still needs to enter a link parameter, continue with URL Encoder and Decoder for percent-encoding. When an image needs to become an inline resource for HTML, CSS, or Markdown, first generate a Data URL with Image to Base64 ; for plain text, token fragments, or configuration values, switch to Base64 Encoder and Decoder for a Base64 round-trip check.

Best practices

HTML entity issues usually come from context confusion, double encoding, and manual handling layered on top of template-engine escaping.

  • First confirm whether the content enters an HTML text node, an attribute value, or another format. Different positions need different rules.
  • Check whether the text already contains entities before encoding. Re-encoding entity text commonly converts ampersands again.
  • Visible product copy usually only needs special-character escaping. Extensive entity output fits legacy systems, email source, or explicit entity-output requirements.
  • Template engines often escape by default. Do not manually encode and automatically escape the same content unless you intentionally need a second text-display layer.
  • Decoding is useful for inspection, but do not insert decoded untrusted HTML directly into a page or hand it to uncontrolled HTML rendering APIs.
  • If you need to allow some tags, use a mature HTML sanitizer and explicitly allow the tags, attributes, and protocols you accept.
  • If content crosses into URL, JSON, JavaScript, or CSS, apply the correct encoding again at that boundary.
  • Before shipping, run a small encode and decode round-trip to confirm symbols, multilingual text, and emoji were not removed or encoded twice.

Limitations

HTML entity conversion solves character representation. It is not a complete content security strategy.

  • HTML entity encoding is not encryption and not access control. Anyone can decode it.
  • HTML entity encoding is not complete XSS protection. Real pages still need context-aware escaping, HTML sanitization, CSP, and safe rendering patterns.
  • This tool decodes using HTML5 entity rules from the entity library. Unknown entities usually remain unchanged instead of raising an error.
  • Special-character mode focuses on HTML structure-sensitive characters. It does not try to rewrite normal text, emoji, or most symbols.
  • Extensive HTML5 entity mode can make output longer because more supported characters may be represented as named or numeric entities.
  • Do not insert decoded untrusted HTML into a page as content, especially through uncontrolled HTML injection APIs.
  • Inputs in the tens of MB can make textareas and clipboard operations slow. Use scripts or streaming workflows at that size.

FAQ

Practical answers about encode range, double encoding, security boundaries, attribute text, and local processing.

Are HTML encoding and HTML escaping the same thing?

They are often used interchangeably in everyday work. Here, encoding means converting characters that affect HTML parsing into entities, such as angle brackets, quotes, and ampersands. In production code, you still need to treat text nodes, attributes, scripts, and styles as separate contexts.

Why does the ampersand need to be encoded first?

The ampersand starts an entity. If it is left alone, entity-like text may be parsed further by the browser or become ambiguous during another processing pass.

Why do I see ampersands converted more than once?

That usually means the content was encoded twice. The first pass changed the ampersand into an entity, and the second pass encoded the ampersand inside that text again. Decode once to inspect the original content.

What is the difference between special-character and extensive modes?

Special-character mode focuses on the characters that commonly affect HTML parsing, such as angle brackets, quotes, apostrophes, and ampersands. Extensive mode uses broader HTML5 entity output for more supported symbols and characters.

Does decoding execute HTML or scripts?

No. The tool only converts entities into text characters. It does not insert the result into the page for execution. You still should not render decoded untrusted HTML directly in an application page.

Can this tool prevent XSS?

Not by itself. Entity encoding is one part of context-aware escaping, but XSS defense also depends on safe templates, sanitizers, CSP, trusted boundaries, and correct rendering APIs.

Which characters should be encoded inside attributes?

At minimum, encode quotes, apostrophes, ampersands, and angle brackets. The exact rules also depend on how the attribute is quoted, whether it is a URL attribute, and whether your template engine already escaped the value.

Does my content leave the browser?

No. Encoding, decoding, copying, and using output as input all run inside the current browser tab. The input is not sent to a server.

Related tools

Continue with adjacent tasks: place entity text in URL parameters, turn images into Data URLs, or check Base64 round trips for plain text.