What is the day of the year?

It is the position of a date within its year, counting January 1st as day 1. December 31st is day 365, or day 366 in a leap year. It is also called the ordinal date.

How are leap years handled?

A year is a leap year if it is divisible by 4, except century years, which must be divisible by 400. So 2024 and 2000 are leap years, but 1900 and 2100 are not. In leap years, March 1st is day 61 instead of day 60.

Is the day of year the same as the Julian date?

Not exactly. The day of year (ordinal date, as in ISO 8601 YYYY-DDD) counts from 1 each January. The astronomical Julian Day Number counts continuously from a fixed point in history. This tool gives the ordinal day within the year.

Is my date sent anywhere?

No. The calculation runs locally in your browser with JavaScript — nothing is transmitted or stored.

DAY OF YEAR CALCULATOR

Find the day number of any date, days left in the year, or turn a day number into a date. Nothing leaves your browser.

Date

Day of the yearDay 283of 365 in 2026 · 82 days remaining

Saturday. 2026 is not a leap year.

Day number to date

Day 100 of 2026 is Friday, April 10.

How to use the day of year calculator

1
Pick a date, or click "Today" to use the current date.
2
Read the day-of-year number, days remaining, weekday, and whether it is a leap year.
3
To go the other way, enter a year and a day number in the lower box.
4
Read the matching calendar date and weekday.

Questions

What is the day of the year?: It is the position of a date within its year, counting January 1st as day 1. December 31st is day 365, or day 366 in a leap year. It is also called the ordinal date.
How are leap years handled?: A year is a leap year if it is divisible by 4, except century years, which must be divisible by 400. So 2024 and 2000 are leap years, but 1900 and 2100 are not. In leap years, March 1st is day 61 instead of day 60.
Is the day of year the same as the Julian date?: Not exactly. The day of year (ordinal date, as in ISO 8601 YYYY-DDD) counts from 1 each January. The astronomical Julian Day Number counts continuously from a fixed point in history. This tool gives the ordinal day within the year.
Is my date sent anywhere?: No. The calculation runs locally in your browser with JavaScript — nothing is transmitted or stored.