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Code Tools

Format, validate, and encode code and data. JSON, YAML, Base64, and more.

Code tools handle the formatting and validation tasks that slow down development work. Paste in a messy YAML config and get it back clean and indented. Validate a JSON payload without opening a terminal. Encode or decode a Base64 string on the fly. These tools are designed for speed — no IDE, no CLI, no setup. Just open the tool, paste your code, and get a clean result. Everything runs in your browser, so sensitive config files stay on your machine.

Code Tools11 tools

Regex Tester

Free online regex tester. Test regular expressions against any text with live match highlighting. Supports global, case-insensitive, multiline, and dotAll flags. Shows all matches with capture groups. No signup required.

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YAML Formatter

Format, validate, and convert YAML online. Instant syntax highlighting, configurable indent, JSON output. Free — no signup required.

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JSON Formatter

Free JSON formatter and validator. Paste any JSON to format it with 2-space, 4-space, or tab indentation. Validates JSON syntax and shows errors inline. Sort keys alphabetically. 100% client-side.

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Markdown to HTML Converter

Free Markdown to HTML converter. Type or paste Markdown and see the rendered preview and raw HTML side by side in real time. Supports GitHub Flavored Markdown: tables, code blocks, strikethrough, and more. No signup required.

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CSS Minifier & Beautifier

Free CSS minifier and beautifier. Paste your CSS and minify it to reduce file size — removes comments, whitespace, and unnecessary characters. Or beautify minified CSS to make it human-readable again. No signup required.

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HTML Formatter & Minifier

Free HTML formatter and minifier. Paste any HTML and beautify it with clean indentation to make it readable, or minify it to remove whitespace and reduce file size. No signup required.

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JSON to CSV Converter

Free JSON to CSV converter. Paste a JSON array of objects and convert it to CSV instantly. Supports nested objects (dot-notation keys), custom delimiters (comma, semicolon, tab), and header row toggle. No signup required.

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CSV to JSON Converter

Free CSV to JSON converter. Paste any CSV and convert it to a JSON array of objects instantly. Auto-detects comma, semicolon, or tab delimiters. Numbers and booleans are typed correctly. Choose pretty or minified output. No signup required.

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HTML to Markdown Converter

Free HTML to Markdown converter. Paste any HTML and instantly get clean Markdown output. Converts headings, bold, italic, links, lists, tables, code blocks, and blockquotes. No signup required.

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JWT Decoder

Free JWT decoder. Paste any JSON Web Token and instantly see the decoded header, payload, and expiry time. Shows all claims in a readable format. No signature verification — 100% client-side. No signup required.

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XML to JSON Converter

Free XML to JSON converter. Paste any XML and get clean, formatted JSON output instantly. Preserves attributes, nested elements, and values. No signup required.

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What are code tools?

Code tools are lightweight browser utilities that format, validate, convert, or inspect code and structured data — without requiring an IDE, terminal, or any installed software. They handle tasks that come up constantly in development work: prettifying a minified JSON response, validating a YAML config before deploying, converting between data formats, or checking syntax errors in a payload. Because they run entirely in your browser, no code or config data is ever uploaded or stored.

Common uses for online code tools

Code tools save time on repetitive formatting and validation tasks that come up throughout the development workflow:

  • Formatting and validating JSON payloads from API responses, logs, or configuration files
  • Prettifying YAML configs that have been minified or poorly indented
  • Converting between JSON and YAML when switching between config formats
  • Encoding and decoding Base64 strings for debugging authentication headers or data URIs
  • Checking syntax errors in structured data before committing or deploying
  • Quickly inspecting or reformatting data from clipboard without opening a full code editor