About ZenCountdown

ZenCountdown is a small, focused suite of date and time calculators: days between dates, countdowns, business days, add/subtract, and age. Every tool runs entirely in your browser — nothing you type is ever sent to a server, and none of the core tools require an account.

We built it because the existing calculator sites people rely on every day haven't meaningfully changed their design or mobile experience in years. ZenCountdown is our attempt at the version of these tools we'd actually want to use: fast, uncluttered, and built for a phone screen first.

What we won't do

We won't put ads between your input and your answer, require sign-up for basic tools, or sell the data you enter — because you don't enter any data we could sell; it never leaves your device.