Date and Time Calculator

Comprehensive collection of calculators for date and time calculations

Date Calculations

Days between dates Popular
Calculate the exact number of days between any two dates
Add days Popular
Add a specific number of days to a given date
Subtract days
Subtract a specific number of days from a given date

Time Calculations

Time difference Popular
Calculate the time difference between two times
Add time
Add multiple time periods to get a total time
Subtract time period
Subtract one time period from another

Mathematical Time Operations

Multiply time period
Multiply a time period by a factor
Divide time period
Divide a time period by a divisor
Time period ratio
Calculate the ratio between two time periods

Percentage Time Calculations

Time period to percentage
Calculate the percentage share of a time period
Percent of time period
Calculate the percentage value from a given time period

Time Unit Conversion

Convert time units Popular
Convert between different time units (seconds, minutes, hours, etc.)

About Date and Time Calculations

Date and time calculations are essential in many areas of daily life and science. These calculators help with:

  • Project Management - Time planning
  • Work Time - Hour calculations
  • Travel Planning - Time zone calculations
  • Science - Time-based analyses
  • Production Planning - Cycle times
  • Human Resources - Time tracking
Important Time Units
Basic Units
1 minute = 60 seconds
1 hour = 60 minutes
Daily Units
1 day = 24 hours
1 week = 7 days
Monthly Units
1 month ≈ 30.44 days
1 year = 12 months
Yearly Units
1 year = 365.25 days
1 decade = 10 years
Tip: Be especially careful with date calculations during leap years. Leap years occur every 4 years, except for years divisible by 100 but not by 400.

Practical Application Examples

Project Management
  • Milestones: Days between deadlines
  • Work time: Hour calculations
  • Deadlines: Remaining days
Human Resources
  • Vacation: Available vacation days
  • Overtime: Time accounting
  • Shift planning: Working hours
Production
  • Cycle times: Production speed
  • Machine utilization: Operating hours
  • Maintenance intervals: Planning times
Science
  • Experiments: Measurement intervals
  • Data analysis: Time series
  • Statistics: Time-based evaluations
Quick Reference
1 day = 24 h
Basic unit
1 h = 60 min
Hour
1 min = 60 s
Minute
1 year ≈ 365.25 days
Calendar year
1 week = 7 days
Week
Time Zone Info
UTC: Coordinated Universal Time
EST: UTC - 5 hours
PST: UTC - 8 hours
GMT: Greenwich Mean Time
CET: UTC + 1 hour