NetworkCalc
FreemiumLiveLast verified 24 Sept 2026
REST utilities for IP subnet math, DNS/WHOIS/SPF lookups, TLS certificate checks, and encoding conversions.
Example request
curl -s 'https://networkcalc.com/api/dns/lookup/google.com'
Free tier, in plain English
Core calculators (subnet, DNS, WHOIS, SPF, binary, encoder, TLS certificate) are free with no key. Paid 'Pro' plan adds domain monitoring and scheduled reports.
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