Days Between Dates
Free date calculator to count days, weeks, months, and years between any two dates. Track deadlines and plan events with precision.
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Calculate Time Between Any Two Dates
Planning an event? Tracking a deadline? Counting down to something special? Our days-between calculator tells you exactly how much time separates any two dates—in days, weeks, months, and years. Never miscalculate another deadline or anniversary again.
Understanding Date Differences
Calculating the difference between dates involves more than simple subtraction because months have different lengths, leap years add extra days, and time zones can affect the exact count. Our calculator handles all these complexities automatically. Date math is essential for project management, event planning, financial calculations (interest, due dates), and legal matters where exact day counts matter. Leap years follow the Gregorian calendar rule (divisible by 4, except centuries not divisible by 400), and dates are handled per the ISO 8601 standard, so counts stay exact across month and year boundaries.
Basic Concept
Days Between = End Date - Start DateHow to Calculate Days Between Dates
Enter your start date using the date picker.
Enter your end date (can be before or after the start date).
View the exact difference in multiple time units.
Use the results for planning, tracking, or documentation.
Date Calculation Scenarios
Project Management
Calculate project durations, milestone timelines, and deadline countdowns — and read the working-day (weekday) count directly for payroll, PTO, or SLA windows.
Travel Planning
Count days until departure, trip length, and time until return.
Financial Planning
Calculate interest periods, payment due dates, and investment timeframes.
Personal Milestones
Track anniversaries, count days since important events, or plan celebrations.
Why Use Our Date Calculator?
Multiple Time Units
See the difference in days, weeks, months, and years—all calculated accurately.
Handles Complexity
Automatically accounts for leap years, varying month lengths, and calendar quirks.
Two-Way Calculation
Works for past dates (how long ago) and future dates (how long until).
Frequently Asked Questions
By default, we calculate the difference between dates (end minus start), which doesn't include both endpoints. If you need to count both days inclusively (like counting vacation days), add 1 to the result.
Our calculator automatically accounts for leap years. February 29th is included when calculating across leap years. A year spanning a leap year (like Feb 1, 2024 to Feb 1, 2025) would be 366 days instead of 365.
Calendar days count every day including weekends; business days count only Monday through Friday. This calculator shows both automatically—alongside the total it breaks your date range into weekdays (business days) and weekend days, so you can read the working-day count directly without excluding weekends yourself. Public holidays aren't deducted, since those vary by country.
Month calculations can vary because months have different lengths (28-31 days). We calculate complete months between dates—from the 15th of one month to the 15th of the next is exactly one month, regardless of whether it spans 28, 30, or 31 days.