HTML Formatter & Minifier
Indent messy HTML so it is readable, or strip whitespace and comments to shrink it. Includes...
Developer Software
Formatters, converters and decoders for everyday development work: JSON, HTML, CSS and JavaScript formatters, Base64, URL and JWT tools, hash and UUID generators, a regex tester and a few server checks. Most of these run in your browser, so what you paste does not leave the page.
JSON Validator & Syntax Linter
Check whether a piece of JSON is valid. See the parser's error message, and fix trailing...
JSON Formatter & Beautifier
Paste JSON, format it with 2 or 4 spaces, minify it, or check it for errors....
Website Technology Stack Detector
Detect the CMS, JavaScript frameworks, analytics and CDN a site uses from its public headers and...
Bulk Multiple URL Opener
Paste a list of web addresses, one per line, and open them all in new tabs...
SSL / TLS Certificate Checker
Connect to a host on port 443 and read its SSL/TLS certificate: issuer, valid dates, days...
Server Status & HTTP Reachability Checker
Check whether a site is reachable from this server: DNS resolution, TCP connection, HTTP response code...
Web Hosting & Server Provider Checker
Find the likely hosting provider of a website from its IP address, network owner and reverse...
DNS Records Lookup
Look up the DNS records for a domain: A, AAAA, CNAME, MX, TXT, NS or SOA....
What Is My User Agent?
See your browser's user agent string and what it says about your browser, version, operating system...
Technical notes
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