Developer Tools
Format and validate JSON, XML and HTML, minify CSS, test regular expressions, preview Markdown and front-end code, and look up DNS records.
11 free tools · no sign-up required
Code Beautifier
Re-indent JavaScript, SQL, JSON, HTML, CSS and XML code
JSON Formatter & Validator
Validate, pretty-print or minify JSON
XML Validator
Check that XML is well-formed and see where it breaks
Markdown Editor
Write Markdown with a live GitHub-style preview
Live Code Editor
Edit HTML, CSS and JavaScript with a live preview
CSS Gradient Generator
Build linear and radial CSS gradients visually
Regex Tester
Test JavaScript regular expressions with live highlighting
HTML Beautifier & Minifier
Beautify or minify HTML markup
CSS Minifier & Beautifier
Minify CSS or turn minified CSS back into readable rules
XML Formatter
Pretty-print or minify XML with your choice of indent
DNS Lookup
Look up A, AAAA, CNAME, MX, TXT, NS, SOA and CAA records
About these tools
These are the small utilities developers reach for many times a day. Paste minified JSON to make it readable and find the line with a syntax error, check whether an XML document is well-formed, tidy up HTML, minify a stylesheet, or try a regular expression against sample text before putting it in code.
Everything except the DNS lookup runs locally in your browser, so pasted code is not sent anywhere. The DNS lookup queries Google Public DNS over HTTPS for the domain you enter, which is the only way to see live DNS records from a web page.
Typical uses
Examples of everyday tasks these tools are built for.
Debugging APIs
Formatting a JSON response to read it, or validating an XML payload before sending it.
Front-end work
Prototyping a snippet of HTML, CSS and JavaScript with a live preview, or generating a CSS gradient.
Going live with a domain
Checking that A, CNAME, MX or TXT records have the values you expect after changing DNS settings.
Frequently asked questions
Is the code I paste stored anywhere?
No. The formatters, minifier, regex tester and editors process text in your browser and do not send it to FlexyPdf. Only the DNS lookup makes a network request, to Google Public DNS.
Which regular expression syntax does the regex tester use?
JavaScript (ECMAScript) regular expressions, as implemented by your browser. Patterns written for other engines such as PCRE or Python may behave differently.
Can I use the output in production?
Yes, but treat it like any other generated code: review it and test it in your project, especially minified CSS.