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Time / Compare timelines

Date Difference Calculator

Measure the exact distance between two dates. Plan project schedules, track countdowns, or calculate eligibility windows in years, months, and days.

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Calculator

Follow the steps below and update the fields to see instant results.

Difference results

Results update instantly as you change the inputs.

Years0
Months1
Days0
Total days31
Negative totals mean the end date is earlier than the start date.

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Timeline overview

Visualize the duration between the two selected dates.

10/15/202511/15/2025

Timeline scaled against a one-year span for a quick visual comparison.

How it works

Date differences use calendar math. We subtract the start date from the end date, count full years, and then portion out the remaining months and days. The total day count uses 24-hour increments so it aligns with scheduling software.

When the end date is earlier than the start date you will see negative totals. This is useful for figuring out how far back a deadline or milestone occurred.