📅 日期时间计算器Date/Time Calculator
在某个日期时间上加减天 / 小时 / 分钟。本地处理。Add or subtract days, hours and minutes from a date-time. Processed locally.
使用说明与常见问题How-to & FAQ
「日期时间计算器」是什么？What is the Date/Time Calculator tool?
在某个日期时间上加减天 / 小时 / 分钟。本地处理。Add or subtract days, hours and minutes from a date-time. Processed locally.
如何使用「日期时间计算器」？How do I use the Date/Time Calculator tool?
在「日期时间计算器」中，按需设置「基准」、「天」、「小时」、「分钟」、「方向」等选项，然后点击「计算」、「复制」按钮即可。In the Date/Time Calculator: Set "Base", "Days", "Hours", "Minutes", "Direction", then click "Compute", "Copy".
时区与夏令时？Time zone and DST?
按浏览器本地时区解释 datetime-local。「天」按日历日加减：跨夏令时切换时保持同一钟点；「小时 / 分钟」按实际经过的时间加减，跨切换时钟点会差 1 小时。datetime-local is read in the browser's local zone. Days are added as calendar days, so the wall-clock time stays the same across a DST change; hours and minutes are elapsed time, so across a DST change the clock time shifts by the 1-hour difference.
示例？Example?
2024-02-28 21:30 加 1 天 2 小时 45 分钟 = 2024-03-01 00:15（2024 年是闰年）。2024-02-28 21:30 plus 1 day 2 hours 45 minutes = 2024-03-01 00:15 (2024 is a leap year).
输入规则？Input rules?
天 / 小时 / 分钟须为整数（留空按 0）；结果须在 0001–9999 年之间，否则显示错误。改动任何输入会自动重新计算。Days, hours and minutes must be whole numbers (blank = 0); the result must fall in years 0001–9999 or an error is shown. Changing any input recalculates automatically.
「日期时间计算器」免费吗？需要注册吗？Is the Date/Time Calculator free? Do I need an account?
「日期时间计算器」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 Date/Time Calculator is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.