Free Browser-Based Tools for
IT Admins & Sysadmins
No signups, no paywalls, no fluff. Just fast, reliable utilities that run entirely in your browser.
Subnet calculators, DNS lookups, SSL checkers, JSON formatters, regex testers, and more. Every tool runs client-side. Your data never leaves your machine.
Featured Tools
The most-used utilities, ready to go.
Subnet/CIDR Calculator
Calculate network address, broadcast address, usable hosts and more from any IP/CIDR input.
DNS Lookup
Query A, AAAA, MX, TXT, CNAME, NS, SOA, and PTR records for any domain.
HTTP Headers Checker
Inspect any URL's response headers and analyse security header configuration.
JSON Formatter & Validator
Format, validate, and minify JSON instantly. Shows precise error locations for invalid input.
Base64 Encoder/Decoder
Encode text or files to Base64, decode Base64 strings, with URL-safe and UTF-8 support.
Regex Tester
Test regular expressions in real time with match highlighting, capture groups, and position info.