One tab, every tool you need.
Subnet math, DNS lookups, SSL checks, port scanning, JWT decoding, and 100+ more.
Instant results, shareable links, free forever.
No account · No ads · No tracking · No rate limits · Free for humans
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Built for engineers
Instant results
Every calculation runs in your browser - no server round-trip, no waiting.
Shareable URLs
Every result has a unique link. Share a subnet layout or IP lookup with one click.
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Designed for engineers who live in terminals. Easy on your eyes at 2am.
No login, no ads
Free forever. No account required, no tracking, no advertisements.
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The one-stop shop engineers actually want.
Free networking and security tools for engineers, sysadmins, and DevOps teams. Subnet calculator, CIDR planner, DNS lookup, SPF checker, DMARC checker, port scanner, SSL certificate checker, HTTP security headers, IP geolocation, JWT decoder, traceroute, and 100+ more - all instant, all free, no account required.
Used by network engineers to debug DNS propagation, sysadmins to validate email security records, and developers to inspect HTTP headers and decode tokens. Every result has a shareable URL. Works in any browser, no login, no ads, no rate limits.