📅 递增日历日期Increment Calendar Date
把每行日期加上若干天、月或年（可批量，月末自动对齐，最多到 9999-12-31）。本地处理。可设置「数量」、「单位」。Add days, months or years to each date (batch; month ends are clamped; up to 9999-12-31). Processed locally. Settings: Amount, Unit.
使用说明与常见问题How-to & FAQ
「递增日历日期」是什么？What is the Increment Calendar Date tool?
把每行日期加上若干天、月或年（可批量，月末自动对齐，最多到 9999-12-31）。本地处理。可设置「数量」、「单位」。Add days, months or years to each date (batch; month ends are clamped; up to 9999-12-31). Processed locally. Settings: Amount, Unit.
如何使用「递增日历日期」？How do I use the Increment Calendar Date tool?
每行输入一个 YYYY-MM-DD 日期，填写“数量”并选择单位（天、月或年），下方即显示加上之后的日期。Enter one YYYY-MM-DD date per line, fill in Amount and pick a unit (days, months or years); the later dates appear below.
可以加月或加年吗？Can I add months or years?
可以，在“单位”里选择天、月或年。目标月份没有那一天时取该月最后一天，例如 2024-01-31 加 1 个月 = 2024-02-29。Yes, choose days, months or years under Unit. When the target month is too short for the day, the last day of that month is used; for example 2024-01-31 plus 1 month is 2024-02-29.
结果超过 9999 年会怎样？What if a result goes past 9999?
会报错并指出是第几行，不会输出 5 位年份。You get an error naming the line; a 5-digit year is never produced.
可以一次处理很多日期吗？Can I process many dates at once?
可以，每行一个日期，空行会跳过，几千行也能即时完成；格式不对的行会报出行号。“数量”留空按 1 计算。Yes. One date per line, blank lines are skipped and thousands of lines finish instantly; an invalid line is reported with its line number. An empty Amount counts as 1.
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「数量」设为 1，输入 2020-01-15，输出为：2020-01-16。With "Amount" set to 1, the input 2020-01-15 becomes 2020-01-16.
有哪些选项可以调整？What options can I adjust?
「递增日历日期」的设置：「数量」默认 1；「单位」可选 天、月、年（默认 天）。每次生成结果都按当前设置处理。Settings in the Increment Calendar Date tool — "Amount" default 1; "Unit": Days, Months, Years (default Days). The result always uses the current settings.
「递增日历日期」免费吗？需要注册吗？Is the Increment Calendar Date tool free? Do I need an account?
「递增日历日期」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 Increment 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.