Day of Year Calculator

Calculate the current day of year. Find out what day number it is today and see how much of the year has passed.

Current Day of Year

About Day of Year

The day of year (also called "day number" or "ordinal date") is the sequential day number within a year, ranging from 1 to 365 (or 366 in leap years). Day 1 is January 1st, and the last day is December 31st.

This is useful for:

  • Scientific calculations and data analysis
  • Astronomical observations
  • Progress tracking throughout the year
  • Database indexing and queries

Get Day of Year in Programming

Learn how to calculate the day of year in various programming languages, databases, and spreadsheet applications:

Spreadsheets

Microsoft Excel
=TODAY()-DATE(YEAR(TODAY()),1,0)
microsoft

Calculates day number starting from Jan 1. Returns the day of year (1-365 or 1-366).

Programming Languages & Databases

Python
from datetime import datetime
day_of_year = datetime.now().timetuple().tm_yday
print(day_of_year)
python

tm_yday returns the day of year (1-366).

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Frequently Asked Questions

What is the day of the year?

The day of the year is a number from 1 to 365 (or 366 in leap years) representing which day of the year a specific date falls on. January 1st is day 1, and December 31st is day 365 or 366.

How do I calculate the day of the year in my programming language?

This page provides code examples for calculating the day of the year in various programming languages including JavaScript, Python, Java, PHP, and more. Each example shows how to get the day number using standard date libraries.

What is the difference between day of year and day number?

Day of year and day number are the same thing - they both refer to the sequential day number within a year, starting from 1 on January 1st.

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