Tool directory
Browse all FreeSEOTools.com tools
Explore practical tools for SEO, writing, image optimization, and PDF tasks, all organized into simple categories.
JSON Formatter & Validator
Format, beautify, and validate JSON data with syntax highlighting and error detection.
Base64 Encode / Decode
Encode text to Base64 or decode Base64 strings back to plain text instantly.
UUID Generator
Generate random UUID v4 identifiers for databases, APIs, and testing workflows.
JWT Decoder
Decode and inspect JSON Web Token headers and payloads without sending them to a server.
Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa.
Regex Tester
Test regular expressions against sample text with real-time match highlighting.
Cron Expression Generator
Build and explain cron schedule expressions with a visual interface.
Diff Checker
Compare two blocks of text side by side and highlight the differences.
Markdown to HTML
Convert Markdown text to clean HTML with a live preview.
Hash Generator
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes from text input in your browser.
HTML Minifier
Minify HTML by removing comments, whitespace, and optional quotes for smaller pages and faster loading.
CSS Minifier
Minify CSS by stripping comments, blank lines, and excess whitespace to ship smaller stylesheets.
JavaScript Minifier
Minify JavaScript by removing comments and unnecessary whitespace for faster page loads.
URL Encoder / Decoder
Encode or decode URL components and full URLs (percent-encoding) for safe links, query strings, and APIs.
Credit Card Validator
Validate credit card numbers using the Luhn checksum and detect the card brand (Visa, Mastercard, Amex, Discover, JCB).
HTTP Headers Checker
Inspect HTTP response status, redirect chain, and security headers for any public URL — including HSTS, CSP, and X-Frame-Options.
DNS Records Lookup
Look up A, AAAA, MX, TXT, NS, CNAME, SOA, and CAA DNS records for any domain using public Cloudflare and Google resolvers.
WHOIS Lookup
Run a public WHOIS / RDAP lookup on any domain to see registrar, registration dates, expiration, status flags, and nameservers.
SSL Certificate Checker
Inspect a domain's SSL/TLS certificate chain, expiry date, issuer, fingerprint, and protocol — useful for catching expiring or misconfigured certs.