Developer Tools
Free Online Developer Tools
Use developer tools for quick formatting, testing, and debugging tasks.
Format, encode, decode, validate, and inspect common developer data.
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Browse tools in this section
JSON Formatter
Format, validate, and pretty-print JSON so it is easier to read and fix.
Base64 Encoder
Encode plain text into Base64 format for testing, transfer, or quick data handling.
Base64 Decoder
Decode Base64 strings back into readable text.
CSS Minifier
Minify CSS by removing extra whitespace and comments.
HTML Minifier
Minify HTML with a clearly scoped online cleanup workflow.
URL Encoder
Encode URL components safely for links and query strings.
URL Decoder
Decode percent-encoded URL text into readable form.
Regex Tester
Test regular expressions against sample text and check matches before using them elsewhere.
JSON to CSV Converter
Convert JSON data into CSV output locally in the browser.
CSV to JSON Converter
Convert CSV data into JSON format locally.
HTML to Markdown Converter
Convert HTML markup into Markdown text.
Markdown to HTML Converter
Convert Markdown text into HTML output.
Featured tools
Start with the strongest options
JSON Formatter
Format, validate, and pretty-print JSON so it is easier to read and fix.
Open tool
Markdown to HTML Converter
Convert Markdown text into HTML output.
Open tool
Base64 Encoder
Encode plain text into Base64 format for testing, transfer, or quick data handling.
Open tool
Base64 Decoder
Decode Base64 strings back into readable text.
Open tool
CSS Minifier
Minify CSS by removing extra whitespace and comments.
Open tool
HTML Minifier
Minify HTML with a clearly scoped online cleanup workflow.
Open tool
Category overview
Format, encode, decode, validate, and inspect common developer data.
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Category FAQ
Questions about Developer Tools
What kind of tools are in Developer Tools?
Developer Tools includes tools for common tasks in this category, all collected in one place.
Are all developer tools fully local?
Some tools run right in your browser, while others may need an online request to finish the job.
How do I find related tools outside Developer Tools?
Use the related categories and links on this page to find similar tools.
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