The small time tools, in one place

Four things developers look up constantly: what a unix timestamp means, what a cron expression actually does, how many working days lie between two dates, and how long a duration really is.

A cron expression, explained in words

Paste a cron string and read what it does in English, including the next few times it will fire. Most cron mistakes are not syntax errors — they are expressions that parse perfectly and run at a completely different time from the one intended, which no validator can catch.

Business days are a calendar question, not arithmetic

Counting working days means excluding weekends and the holidays that apply to you, which are not the same anywhere. The holidays are yours to state rather than ours to assume, because a tool that quietly applies one country’s calendar to another’s deadline is worse than one that asks.

Questions

Why does the difference between two time zones change during the year?

Because countries change their clocks on different dates. The United States moves in March and November, the European Union in the last weekends of March and October, and the southern hemisphere moves the opposite way entirely. For a few weeks each year the usual gap is an hour out, which is when most mis-scheduled calls happen.

Can I use this offline?

The tools themselves are arithmetic in your browser, so once the page has loaded the timer, stopwatch and converter keep working without a connection. Anything that syncs obviously does not.