Date & Time Calculators
Fast calendar math,
without the clutter.
Use Calcadian to calculate dates, days, weeks, workdays, ages, time durations, and timestamps instantly.
Popular calculators
The tools people reach for most.
Date Difference Calculator
Count days, weeks, months, and years between two dates.
Add or Subtract Days Calculator
Find a future or past date by adding or subtracting time.
Business Days Calculator
Count working days between two dates, excluding weekends.
Age Calculator
Calculate exact age from any date of birth.
Date calculators
Date Difference Calculator
Count days, weeks, months, and years between two dates.
Add or Subtract Days Calculator
Find a future or past date by adding or subtracting time.
Business Days Calculator
Count working days between two dates, excluding weekends.
Age Calculator
Calculate exact age from any date of birth.
Week Number Calculator
Find the ISO week number for any date.
Days Until Calculator
Count how many days are left until any future date.
Time calculators
Why use Calcadian?
Fast
Lightweight pages and instant results — no loading spinners.
Clean
No clutter, no popups, no distractions. Just the math you need.
Private
Calculations run in your browser. Your dates stay with you.
Mobile-first
Designed for thumbs and small screens before desktop.