Fieldnotes brings together a few everyday web utilities and the explanations needed to read their results.
The subnet calculator works with the numbers you enter. The URL inspector uses the browser’s URL parser to break an address into parts. Neither tool connects to the addresses being inspected.
The tools have no account system and no saved workspace. Reloading or leaving a page discards its current input.
Calculations run in your browser. Input is not submitted to an application server. There are no analytics scripts, third-party fonts, cookies or browser-storage features on these pages.
Loading the website still requires normal web requests to this server. As with any website, your connection and browser send network information needed to deliver the pages. Do not confuse local processing with anonymity.
Output is for reference. A URL structure is not a security check, a calculated address block is not proof of routing, and this site does not test whether a remote host is reachable.
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