📅 四舍五入日历日期Round Calendar Date

使用说明与常见问题How-to & FAQ

「四舍五入日历日期」是什么？What is the Round Calendar Date tool?

按周/月/年对齐日期（向下、最近或向上）。本地处理。可设置「单位」、「方式」。Align a date to week/month/year (down, nearest or up). Processed locally. Settings: Unit, Mode.

如何使用「四舍五入日历日期」？How do I use the Round Calendar Date tool?

输入日期 YYYY-MM-DD，选择单位（周、月、年）和方式（向下、最近、向上），下方即显示取整后的日期。Enter a date as YYYY-MM-DD and choose a unit (week, month or year) and a mode (down, nearest or up); the rounded date appears below.

向上取整时已经对齐的日期会变吗？Does Up change a date that is already aligned?

不会。已经是周一、月初或年初的日期在三种方式下都保持不变；其他日期向上取整到下一个周一、下月 1 日或下一年 1 月 1 日。No. A date that is already a Monday, the 1st of a month or 1 January stays the same in every mode; other dates round up to the next Monday, the 1st of the next month or 1 January of the next year.

一周从哪天开始？“最近”遇到正中间怎么办？When does a week start, and how are ties handled?

按 ISO 规则一周从周一开始；“最近”在正好位于中间时取较早的那个。Weeks start on Monday as in ISO 8601, and Nearest picks the earlier date when it is exactly halfway.

结果超过 9999 年会怎样？What if the result would pass 9999?

会提示无法向上取整，不会输出 5 位年份。You get a message that it cannot be rounded up; a 5-digit year is never produced.

用的是哪种历法、支持哪些年份？Which calendar and years are supported?

按外推格里高利历（现行公历规则向前沿用）计算，年份为 0001–9999，输出一律为 4 位年份的 YYYY-MM-DD；结果不会超过 9999-12-31。The proleptic Gregorian calendar (today's rules applied backwards) for years 0001 to 9999. Output always uses YYYY-MM-DD with a 4-digit year and never goes past 9999-12-31.

和时区有关吗？Do time zones matter?

无关，这里只处理钟面时间或日历日期，不读取设备时钟，也不考虑夏令时。No. It works on clock readings or calendar dates only, never reads your device clock and ignores daylight saving time.

输入和输出是什么样的？What does the input and output look like?

例如把「单位」设为 月，「方式」设为 向下，输入 2024-03-15，输出为：2024-03-01。With "Unit" set to Month and "Mode" set to Down, the input 2024-03-15 becomes 2024-03-01.

有哪些选项可以调整？What options can I adjust?

「四舍五入日历日期」的设置：「单位」可选 周、月、年（默认 周）；「方式」可选 向下、最近、向上（默认 向下）。每次生成结果都按当前设置处理。Settings in the Round Calendar Date tool — "Unit": Week, Month, Year (default Week); "Mode": Down, Nearest, Up (default Down). The result always uses the current settings.

「四舍五入日历日期」免费吗？需要注册吗？Is the Round Calendar Date tool free? Do I need an account?

「四舍五入日历日期」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Round Calendar Date tool is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.