16 tools we built because we needed them. Almost all of them run entirely in your browser — no account, no rate limit, and nothing about what you look up reaches our servers. Free, and staying that way.
Every prefix /0 to /32 with mask, wildcard, hex and host counts. Printable PDF.
Open tool →MX, SPF, DMARC and DKIM graded, with a link to the fix for each problem.
Open tool →Storage and bandwidth from resolution, frame rate, codec and retention.
Open tool →Whether your switch can actually power the cameras, APs and readers.
Open tool →Are these really free? Yes. No account, no rate limit, no paid tier behind a wall. Most run in your browser rather than on our servers, so they cost us very little.
Do you log what I look up? No. Most of these make no network request at all — disconnect and they keep working. The DNS and email checkers query public resolvers straight from your browser, so nothing of ours sees the query.
Which work offline? Everything except the DNS lookup and email checker. The MAC lookup pulls the IEEE registry once, then works from cache.
Can I embed these on my own site? No — the pages set frame-ancestors and cross-origin resource policies that block framing and hotlinking. Linking to them is very welcome.
Most free tools online are stuffed with ads, gated behind a signup, or quietly logging what you look up — and the IT-adjacent ones are often subtly wrong at the edges, which is worse than useless. We would rather point people at something we trust.
The second reason is that some of you will eventually need someone to actually do the work, and when that happens we would like to be a name you already recognise. That is the whole arrangement. Use the tools, ignore the rest.
If there is something you keep opening a browser tab for, tell us and we will look at building it. Get in touch or call 541-508-8797.