Observed arrival · 2026-11-05
nstool.app: DNS diagnostics, with a command line
A browser-based DNS lookup and diagnostics tool that checks records, authoritative nameservers, public resolver differences, and email DNS configuration.
- For
- People diagnosing domain and email DNS
- Worth noticing
- It checks SPF’s 10-lookup limit and queries each authoritative nameserver directly.
Field notes
The page lays out three diagnostic paths: querying authoritative nameservers directly, comparing the same question across public resolvers, and checking mail-related DNS. Its examples distinguish cached propagation differences from inconsistent authoritative answers, and it describes checking SPF syntax, the 10-lookup limit, DMARC tags, and DKIM selectors. Command-line routes are shown for plain-text results, alongside separate JSON API endpoints.
Observed signals
Read the marks
Editorial observations of this landing page, not a rating.
One card from the complete issue