Free network diagnostic tools for DNS, IP, email and SSL checks
WebAssembly sandbox for running untrusted Python safely
Stage
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Founded
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Based in
IN
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Pricing model
Freemium
Open source
Pricing
Free plan: All 41 tools with unlimited checks, 3 saved domains with daily monitoring, 7 days of history. Pro plan: $29/month for 50 domains, scans every 6 hours, email, Slack, Telegram and webhook alerts, 12 months of history and API access.
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Key features
DNS Lookup - resolve A, AAAA, MX, TXT, NS, CNAME records
Blacklist Checker - query 7 major DNS blocklists
SSL/TLS Certificate Checker - verify certificate chain, expiry and protocol support
Email Deliverability - check SPF, DKIM and DMARC records
WHOIS Lookup - query domain registration details
Reverse DNS (PTR) - check IP to hostname resolution
Port Checker - test common HTTP/HTTPS ports
BIMI Lookup - query BIMI TXT records
Domain monitoring with automated scans
Multi-channel alerts via email, Slack, Telegram and webhooks
Full CPython 3.14 with standard library
Async callbacks from sandboxed code
No filesystem or network unless allowed
Fast startup in 1–5 milliseconds
Embed from Python, JavaScript or Rust
MCP server support
gRPC server deployment
Hosted execution over HTTP and WebSocket
What makes it different
41 tools all available free with unlimited checks
Clear sourcing - every result shows its source and what was not tested
Live DNS queries from edge servers via DNS-over-HTTPS
Domain monitoring and alerts with affordable Pro plan at $29/month
The Network Tools
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