IP

Subnet Calculator

CIDR notation, VLSM breakdown, host counts, and visual subnet maps. Supports IPv4 & IPv6.

networking
DN

DNS Lookup & Propagation

Query A, AAAA, MX, CNAME, TXT, and SOA records. Check propagation across global resolvers.

dns
SS

SSL/TLS Checker

Inspect certificate chains, expiration dates, cipher suites, and HSTS headers for any domain.

security
CR

Cron Expression Builder

Visual cron schedule builder with plain-English translations and next-5-runs preview.

linux
PW

Password & Key Generator

Cryptographically random passwords, SSH keys, and API tokens. Configurable entropy.

security
PT

Port Reference

Searchable database of 6,000+ known ports with service names, protocols, and risk notes.

networking
CS

Sysadmin Command Cheat Sheet

270+ essential one-liners for Linux, Windows, Active Directory, Exchange, Docker, and more. Click to copy.

reference
ST

Cloud Service Status

Live status for AWS, Azure, GCP, M365, GitHub, Cloudflare, Slack, and more. Auto-refreshes every 5 minutes.

cloud