Leap years

Find the calendar of leap years. This electronic calendar allows you to know the years having a February 29.

By adding leap year dates to your calendar, you can schedule reminders so you don't forget years that have 366 days. If your calendar allows you to receive notifications on your phone or by e-mail; you can create reminders so you don't forget February 29 of the leap years.

Leap years are based on the Gregorian calendar, created in 1582 by Pope Gregory XIII. This calendar was designed to correct the errors introduced by the less precise Julian calendar.
In the Gregorian calendar, a classic year consists of 365 days. Since the actual duration of a sidereal year (the time it takes for the earth to turn once around the sun) is actually 365,2425 days. A “leap year” of 366 days is used once every four years to eliminate the error caused by the traditional (shorter) three years. Any year uniformly divisible by 4 is a leap year. For example, 1988, 1992 and 1996 are leap years.
However, the Gregorian calendar states that a year that is uniformly divisible by 100 (e.g. 1900) is a leap year only if it is also divisible by 400.

Years are leap if they are multiple of four, but not if they are multiple of one hundred, except for multiple years of four hundred which are also leap.
Where the years are leap years, the year shall consist of 366 days, with the addition of 29 February.

This ICAL file in ics format can also be integrated into computer programs or systems that do not take into account February 29 of the years. If your system works locally and requires knowledge of leap years, then this file can be imported into your program to help you take into account the 366-day years with a February 29.
You can also find the files in CSV and XLS format.
Data issued subject to legal or regulatory change.

These files are particularly suitable for the country: France / EU

本数据集用于查询闰年日历。该电子日历工具可帮助您识别存在2月29日的年份。
将闰年日期添加至日历后，您可设置提醒，以免遗忘拥有366天的闰年。若您的日历支持通过手机或电子邮件接收通知，还可创建提醒以牢记闰年的2月29日。
闰年规则基于格里高利历（Gregorian calendar），该历法由教皇格列高利十三世于1582年颁布，旨在修正精度较低的儒略历（Julian calendar）所引入的误差。在格里高利历中，平年为365天。由于恒星年（sidereal year，即地球绕太阳公转一周的实际时长）实际为365.2425天，因此每四年增设一个拥有366天的闰年，以抵消传统三年按365天计算所产生的误差。凡可被4整除的年份均为闰年，例如1988年、1992年与1996年。
但格里高利历同时规定，凡可被100整除的年份（如1900年），仅当它同时可被400整除时才可成为闰年。简言之，闰年需满足：可被4整除但不可被100整除，或可被400整除。闰年全年共366天，额外增加2月29日这一日。
本数据集提供ICS格式的ICAL文件，可集成至未考虑2月29日的计算机程序或系统中。若您的本地系统需要获取闰年相关信息，可将该文件导入程序，以辅助识别拥有366天且包含2月29日的年份。此外还可获取CSV与XLS格式的文件。本数据集发布的数据可能因法律法规变动而调整。此类文件尤其适用于法国/欧盟地区。