D-Day Calculator

Calculate how many days remain until a target date, or how many days have passed. Shows weeks, months, hours, minutes, and seconds.

Select a target date to calculate days remaining or elapsed

Today: 2026-02-20

Select a date to calculate
Calculation is based on calendar days from midnight to midnight in your local time zone.

How to Use This Tool

  1. 1

    Select a target date

    Use the date picker to choose your target date — an upcoming event, deadline, birthday, or any date you want to track.

  2. 2

    View the D-Day result

    The calculator instantly shows D-xxx (days remaining) or D+xxx (days past). D-Day means today is the target date.

  3. 3

    Check detailed breakdown

    Below the main result, see the total days expressed as weeks, months, hours, minutes, and seconds.

  4. 4

    Copy the result

    Click the D-Day label to copy it to your clipboard for sharing or saving.

Frequently Asked Questions

What does D-Day mean?
D-Day (or 'D-day') refers to a target date. D-30 means 30 days remain until the date. D+5 means 5 days have passed since the date. D-Day itself means today is the target date.
How is the day count calculated?
The calculator counts full calendar days between today (midnight) and the target date (midnight). Partial days are not included.
Can I use past dates?
Yes. If you select a date in the past, the result will show D+xxx indicating how many days have elapsed since that date.
Does it account for time zones?
The calculation uses your browser's local date. It compares midnight-to-midnight in your local time zone.