Usage Guide

Add or subtract any combination of days, weeks, months, and years from a date to find a future or past date.

1. 1Select Add Days to find a future date, or Subtract Days to find a past date.
2. 2Enter a start date using the date picker — defaults to today.
3. 3Enter the number of days, weeks, months, or years to offset.
4. 4Click Calculate. The result date and day of the week appear instantly.

Calculate the exact gap between two dates — displayed simultaneously in days, weeks, months, and years.

1. 1Enter the start date in the first date field.
2. 2Enter the end date in the second date field.
3. 3Click Calculate to see the interval.
4. 4Results show the gap in days, weeks, months, and years simultaneously.

Live countdown (or count-up) to any date. Updates automatically — no refresh needed.

1. 1Pick or type your target date in the date field.
2. 2The countdown updates automatically — no Calculate button needed.
3. 3If the date has already passed, it shows how many days ago it was.
4. 4Bookmark the page to return to your countdown anytime.

Calculate an exact age down to the second, with a live ticker updating every second.

1. 1Enter your date of birth in the date field.
2. 2Click the Calculate My Age button.
3. 3Your exact age in years, months, and days is displayed.
4. 4A live counter shows your age in hours, minutes, and seconds, updating every second.

Count working days between two dates, or find the date that falls N business days from a start date.

1. 1Count Days mode: enter a start date and an end date, then click Calculate to count working days between them.
2. 2Add Days mode: enter a start date and a number of business days, then click Calculate to find the resulting workday.
3. 3Weekends (Saturday and Sunday) are automatically excluded from the count.
4. 4The result also shows the total calendar days for reference.

Look up the ISO week number for any date, plus quarter, day-of-year, and full calendar breakdown.

1. 1The current week number is shown automatically when you open the page.
2. 2Select any date from the date picker to look up its week number.
3. 3View the ISO week number, quarter, day of year, and full calendar details.
4. 4The year is also shown — useful for dates near the turn of a year.

Bidirectional converter: Unix epoch ↔ human-readable date/time. Supports both seconds and milliseconds.

1. 1Timestamp → Date: enter a Unix timestamp (in seconds or milliseconds) and click Convert.
2. 2Date → Timestamp: switch modes, enter a date and time, then click Convert.
3. 3Use the copy button to copy any result to your clipboard.
4. 4The live counter at the top shows the current epoch time updating in real time.

Estimate your due date and trimester from current pregnancy weeks. Supports natural conception and IVF/blastocyst transfer.

1. 1Choose Natural Pregnancy for standard conception, or IVF for assisted reproduction.
2. 2Natural: enter how many weeks (and optional days) pregnant you currently are.
3. 3IVF: select the embryo transfer stage (Day 3, Day 5, or Day 6), then enter current weeks and days.
4. 4Click Calculate to see your estimated due date, current trimester, and weeks remaining.

Countdown to public holidays in 25+ countries, auto-detected from your IP address.

1. 1Your country is auto-detected from your IP address — no setup required.
2. 2Upcoming public holidays are listed with a live countdown showing days remaining.
3. 3Use the country dropdown to switch to any of the 25+ supported countries.
4. 4Past holidays are dimmed; click Refresh to reload the latest data.