HTML Encoder/Decoder
Free HTML encoder/decoder. Convert special characters to HTML entities and back instantly.
How HTML Encoder/Decoder Works
Encode: converts reserved HTML characters to named or numeric entities (& → &, < → <, > → >, " → "). Decode: reverses HTML entities back to characters.
Use Cases
Calculate html encode html
Get instant html encode html calculations for your html tools analysis and reporting needs.
Verify Your Results
Double-check your manual calculations and validate your html encode html against industry-standard formulas.
Quick Estimates
Make fast estimates and what-if analyses by experimenting with different inputs and seeing instant results.
Export & Share
Calculate results and easily export them for use in spreadsheets, reports, and presentations.
Frequently Asked Questions
What is HTML encoding?
HTML encoding converts special characters to their HTML entity equivalents so they display as characters rather than being interpreted as HTML markup. The five critical characters: & → &, < → <, > → >, " → ", ' → '.
Why is HTML encoding important for security?
Encoding user-supplied content before inserting it into HTML prevents Cross-Site Scripting (XSS) attacks. If a user submits '<script>alert(1)</script>' and it's inserted into the page unencoded, the script executes. Encoding it to <script> displays it as text instead.
Named entities vs numeric entities — what's the difference?
Named: & < > — human-readable, supported in HTML5. Numeric decimal: & < > — universal, works everywhere including XML. Numeric hex: & < > — same as decimal but hex notation. All represent the same characters.
Is my data stored?
No.
Can I use this on mobile?
Yes.
About This Tool
Built by the Calcyo team and last updated June 2026. All calculations follow industry-standard methodology. No data leaves your browser — calculations run entirely client-side using JavaScript. If you spot an error in the formula or benchmark data, email us at support@calcyo.xyz.