Free developer tools
110 quick tools for code, data, images, PDFs and more. They run in your browser, so your files and text stay on your device.
3 tools
DNS Lookup
Query A, AAAA, MX, TXT, CNAME, NS and other records over DNS-over-HTTPS.
Open toolWHOIS / RDAP Lookup
See a domain’s registrar, creation and expiry dates, status and name servers via RDAP.
Open toolIP Subnet Calculator
Calculate network, broadcast, host range and mask for IPv4 CIDR blocks, and split subnets.
Open tool