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Tools for Developers, SEO & the Web
Free tools for everyday web tasks: format code, convert and compress images, work with PDFs, check DNS and HTTP headers, and generate SEO markup. They do real work on real files, and you do not need an account.
84 Tools
7 Categories
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Developer Tools
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.
21 tools
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Base64 Encoder & Decoder
Encode text to Base64 or decode Base64 back to text, with UTF-8 handled correctly. Runs in...
Bulk Multiple URL Opener
Paste a list of web addresses, one per line, and open them all in new tabs...
CSS Formatter & Minifier
Format messy CSS into readable rules or minify it for a smaller file. Includes a live...
DNS Records Lookup
Look up the DNS records for a domain: A, AAAA, CNAME, MX, TXT, NS or SOA....
Hash Generator (MD5, SHA-256, SHA-512)
Hash any text and see MD5, SHA-1, SHA-256, SHA-384 and SHA-512 digests side by side. Runs...
HEX, RGB, HSL & CMYK Color Converter
Convert a color between HEX, RGB, HSL and CMYK with a live preview and color picker....
HTML Formatter & Minifier
Indent messy HTML so it is readable, or strip whitespace and comments to shrink it. Includes...
JavaScript Formatter & Minifier
Indent JavaScript, run a snippet in a sandboxed frame and see console output. The minifier is...
JSON Formatter & Beautifier
Paste JSON, format it with 2 or 4 spaces, minify it, or check it for errors....
JSON to JSON Schema Converter
Paste a sample JSON object and get a draft-07 or 2020-12 JSON Schema inferred from it....
JSON Validator & Syntax Linter
Check whether a piece of JSON is valid. See the parser's error message, and fix trailing...
JWT (JSON Web Token) Debugger & Decoder
Decode a JWT to see its header, payload claims and expiry time. It decodes only and...
Regular Expression (RegEx) Tester
Test a regular expression against sample text, with flags, match highlights and capture groups. Uses the...
Server Status & HTTP Reachability Checker
Check whether a site is reachable from this server: DNS resolution, TCP connection, HTTP response code...
SSL / TLS Certificate Checker
Connect to a host on port 443 and read its SSL/TLS certificate: issuer, valid dates, days...
Unix Timestamp Converter
Convert a Unix timestamp to UTC, local time and ISO 8601, or turn a date into...
URL Encoder & Decoder
Encode text so it is safe in a URL, or decode percent-encoded text. Uses the same...
UUID / GUID Generator (v4)
Generate random version 4 UUIDs, 1 to 50 at a time, with optional uppercase and no...
Web Hosting & Server Provider Checker
Find the likely hosting provider of a website from its IP address, network owner and reverse...
Website Technology Stack Detector
Detect the CMS, JavaScript frameworks, analytics and CDN a site uses from its public headers and...
What Is My User Agent?
See your browser's user agent string and what it says about your browser, version, operating system...
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