Developer tool
Your files never leave your device
Check your Network tab and see
Work starts the moment you drop a file
No daily limit, no sign-up, no watermark
Enough to check a home LAN. Not a full VLSM planner or IPv6 calculator.
Math uses 32-bit unsigned operations in JavaScript. Unusual typed-array issues are unlikely for valid dotted quads.
The tool only does the bitwise math on the address and prefix you enter. It does not query WHOIS, RIR databases, or geo-IP, so nothing about the network leaves the page.
That is the promise behind every tool here. Files are read in your browser tab, processed there, and discarded when you close it — never uploaded to our servers.
Convert Unix epoch timestamps to human-readable dates, and vice versa.
Test, visualize, and debug Regular Expressions instantly in your browser.
Format, validate, prettify and beautify your JSON data instantly.
Generate valid universally unique identifiers (UUIDs/GUIDs) instantly.
MD5 for checksums plus SHA-1, SHA-256, and SHA-512 via Web Crypto — all in your browser, nothing uploaded.
Parse standard 5-field cron expressions, read them in plain English, and see the next five run times.
