Mastering Dates, Deadlines, and Time Zones
Date math looks simple until you actually try it by hand — leap years, varying month lengths, and time zones all quietly introduce off-by-one errors. These tools handle the edge cases so you don't have to think about them.
Ages, durations, and countdowns
The Age Calculator finds an exact age in years, months, and days from a birth date — and works for any reference date, not just today, which is useful for legal or medical contexts. The Days Between Dates tool handles the more general version of the same problem: the exact duration between any two dates, split into weeks, business days, and weekend days.
For anything you're counting down to — a launch, a wedding, a deadline — the Countdown Timer updates live down to the second, and the Deadline Planner breaks a distant date into 25/50/75% milestone checkpoints so a big deadline doesn't sneak up on you.
Business days and time zones
"Add 10 business days" sounds simple until weekends land in the middle — the Business Days Calculator adds or subtracts working days from any start date automatically. For teams spread across regions, the Time Zone Converter shows the current (or any chosen) time across multiple cities at once, which turns "what time works for everyone" from guesswork into a quick glance.
Durations and week numbers
The Time Duration Calculator adds, subtracts, or finds the gap between two clock times — handy for shift schedules or anything measured in hours and minutes rather than days. And if you've ever needed to know exactly which ISO week a date falls in (common in project planning and manufacturing schedules), the Week Number Calculator converts both directions.