Day Counter
Count days between dates, days since or until a date, and countdowns to events. Handles leap years with step-by-step solutions.
Your Input
Select a calculation type, enter your dates, and click Count Days to see results with step-by-step solutions and visualizations.
Day Count Result
Step-by-Step Solution
Complete User Guide
What is a Day Counter?
A day counter calculates the number of days between two dates, days since a past date, days until a future date, or a countdown to an event. It accounts for leap years, varying month lengths, and year boundaries.
Total days = End Date − Start Date | Business days = weekdays only (Mon–Fri)
Use it for project timelines, countdowns, age or tenure in days, and event planning.
Date Format
Use YYYY-MM-DD (e.g. 2025-02-15). Dates from year 1 to 9999 are supported.
Calculation Types
Days Between
Exact number of days between two dates, plus weeks, months, hours, and business days (weekdays only).
Days Since
How many days have passed since a past date (e.g. since birth, since an event).
Days Until
How many days remain until a future date (deadlines, countdowns).
Countdown
Countdown to an event with optional name; shows days, weeks, months, hours, and minutes until the date.
How to Use This Calculator
- Select a calculation type (Days Between, Days Since, Days Until, or Countdown)
- Enter the required dates (and optional event name for Countdown)
- Click 'Count Days' to see the result
- Review the main result, detail cards (when available), and step-by-step solution
- Use the chart for a visual breakdown where available
- Click 'Reset' to set all dates to today and clear results
Understanding Your Results
Main result
The total number of days, with a short formatted summary (e.g. X days, or X weeks Y days).
Detail cards
For Days Between and Countdown: breakdown into weeks, months, business days, and hours where applicable.
Step-by-step
Shows how the day count was calculated, including formulas and intermediate steps.
Understanding Business Days
Business days are weekdays (Monday–Friday); weekends are excluded. Used for project deadlines, shipping, work schedules, and contracts. Holidays are not excluded.
Day Counting Methods
Simple subtraction: Total days = end date − start date.
Relativedelta: Precise years, months, and days; accounts for month lengths and leap years.
Business days: Count of weekdays (Mon–Fri) between the two dates.
Important Notes
- All calculations account for leap years and varying month lengths.
- Business days (Days Between) exclude weekends only; holidays are not excluded.
- Use YYYY-MM-DD format. Dates must be between year 1 and 9999.