# Days until the 25th

Counts the days from today, or any date you choose, to the next 25th of a month, with its date and the 25th after it.

- Page: https://www.acalculator.org/days/days-until-the-25th
- JSON spec: https://www.acalculator.org/days/days-until-the-25th.json
- Version: 5979eef2d55a

## Default answer

Example with the default inputs (Count from October 19, 2026) on the example date Monday, October 19, 2026: From October 19, 2026, there are 6 days until the 25th, Sunday, October 25, 2026.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| from | Count from | The date to count from. Today, unless you change it. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| days | Days until the 25th | Whole days from the start date to the next 25th of a month; 0 when the start date is the 25th. |
| date | Next 25th | The first date on or after the start date that is the 25th of its month. |
| after | The 25th after | The next 25th after that date. |

## Method

Find the first date on or after the start date that is the 25th of its month, then count the days from the start date to it.

## Assumptions

- On the 25th, the count is 0, and the 25th after is the 25th of the next month that has one.
- Every month has a 25th, so the next one is never more than a month away.
- The start date itself is not counted: from the day before, the count is 1.
- Dates are calendar days with no time of day, so a time zone or a daylight-saving change never adds or loses a day.
- Start dates from January 1, 1900 to December 31, 2400 work.

## Worked examples

1. from = 2026-10-19 gives date = 2026-10-25, days = 6, after = 2026-11-25. Source: IETF RFC 3339, section 5.7 (days in each month) and Appendix C (the leap year rule) (https://www.rfc-editor.org/rfc/rfc3339).
2. from = 2026-12-31 gives date = 2027-01-25, days = 25, after = 2027-02-25. Source: IETF RFC 3339, section 5.7 (days in each month) and Appendix C (the leap year rule) (https://www.rfc-editor.org/rfc/rfc3339).
3. from = 2027-02-01 gives date = 2027-02-25, days = 24, after = 2027-03-25. Source: IETF RFC 3339, section 5.7 (days in each month) and Appendix C (the leap year rule) (https://www.rfc-editor.org/rfc/rfc3339).
4. from = 2028-02-15 gives date = 2028-02-25, days = 10, after = 2028-03-25. Source: IETF RFC 3339, section 5.7 (days in each month) and Appendix C (the leap year rule) (https://www.rfc-editor.org/rfc/rfc3339).
5. from = 2027-01-25 gives date = 2027-01-25, days = 0, after = 2027-02-25. Source: IETF RFC 3339, section 5.7 (days in each month) and Appendix C (the leap year rule) (https://www.rfc-editor.org/rfc/rfc3339).

## FAQ

### How many days until the 25th?

It depends on the date, so the count above starts from today as your device shows it. From the 1st of a month that has a 25th, it is 24 days away; on the 25th itself the count is 0. Change “Count from” to count from another date.

### What if today is the 25th?

Then the count is 0, because the next 25th on or after today is today itself. The page also shows the 25th after it, which is 28 to 31 days later.

### Which months have a 25th?

All 12. Every month has at least 28 days, so every month has a 25th.

### How many times does the 25th come in a year?

12, one in every month.

### What day of the week will the 25th be?

It changes from month to month. A 31-day month moves the 25th 3 days later in the week, a 30-day month 2, a 29-day February 1, and a 28-day February 0. The page shows the weekday of the next 25th in its date.

### How are the days until the 25th counted?

From the start date (today, unless you change it) to the next 25th, without counting the start date, in calendar days. Weekends and holidays count like any other day.

## Sources

- IETF RFC 3339, Date and Time on the Internet: Timestamps, section 5.7 (the days in each month) and Appendix C (the leap year rule). https://www.rfc-editor.org/rfc/rfc3339
- U.S. Naval Observatory, Leap Years: the Gregorian leap year rule. https://aa.usno.navy.mil/faq/leap_years
