요금제

날짜 계산기

1월 1일부터 며칠이 지났을까요? 시작 날짜를 1월 1일, 종료 날짜를 오늘로 고르면 셀 수 있습니다. 이 계산기는 두 날짜 사이의 일수를 세거나 날짜에 일수를 더하며, 윤년도 반영합니다.

결과

값을 입력하고 계산을 누르면 결과가 표시됩니다.

공식

days=end−start\text{days} = \text{end} - \text{start}

Dates are counted as whole calendar days, including leap days (the end date is not counted twice).

이 계산기 사용법

  1. Choose the mode and pick the dates.
  2. The difference counts from the start date up to (not including) the end date.

풀이 예제

Days from 1 January to 25 December 2026

25 December is day 359 of 2026, and 1 January is day 1.

So there are 358 days between them: 51 weeks and 1 day.

Easy: days since 1 January, counted on 1 June 2026

January 31 + February 28 + March 31 + April 30 + May 31 = 151 days.

So on 1 June 2026 it had been 151 days since January 1.

Medium: days since January 1, 2025

From 1 January 2025 to 1 January 2026 is 365 days (2025 isn’t a leap year).

From 1 January to 2 November 2026 is 305 more days, so the total is 670 days.

Hard: across a leap day

2024 is a leap year, so February has 29 days.

January 31 + February 29 = 60 days from 1 January to 1 March.

자주 하는 실수

  • Counting both the start and end dates: from 1 January to 2 January is 1 day.
  • Forgetting leap years: years divisible by 4 have 29 February, except century years not divisible by 400.
  • Using 30-day months: real months have 28 to 31 days, so always count the actual calendar.

자주 묻는 질문

How many days ago was January 1?

Put 1 January of this year as the start date and today as the end date. On 2 November 2026, for example, January 1 was 305 days ago.

Are leap years handled?

Yes — every date is converted to an exact calendar day count.

Does it count the end date?

No. From Monday to Tuesday is 1 day. Add 1 if you want to include both ends.