🎂 由年龄推出生年示意Date of Birth from Age (Demo)

使用说明与常见问题How-to & FAQ

「由年龄推出生年示意」是什么？What is the Date of Birth from Age (Demo) tool?

用参考日与整数周岁估算出生年与同月日示意生日。未判断今年是否已过生日，仅示意。本地处理。Estimate birth year and a same-month-day demo DOB from a reference date and whole years of age. Does not check whether the birthday has passed — demo only. Processed locally.

如何使用「由年龄推出生年示意」？How do I use the Date of Birth from Age (Demo) tool?

在「由年龄推出生年示意」中，填写「年龄（周岁）」、「参考日」等参数，结果会随输入实时计算并显示在下方。In the Date of Birth from Age (Demo): Fill in "Age (years)", "Reference date"; results are recalculated instantly as you type.

精确？Exact?

需要完整生日才能算精确年龄。年龄须为 0–120 的整数。Need the full birthday for an exact age. Age must be a whole number from 0 to 120.

闰日怎么处理？What about leap days?

参考日是 2 月 29 日、推得的出生年不是闰年时，示意生日改为该年的 2 月 28 日，不会写出不存在的 2 月 29 日。If the reference date is 29 February and the computed birth year is not a leap year, the demo DOB uses 28 February that year — it never invents a non-existent 29 February.

哪些输入会被检查？Which inputs are validated?

「由年龄推出生年示意」会检查这些输入——「年龄（周岁）」：必须填写；绝对值超过 10¹⁵ 的数也会被拒绝。不符合时结果区显示具体提示，不会给出数字。The Date of Birth from Age (Demo) checks its inputs — "Age (years)": required; numbers above 10¹⁵ in absolute value are rejected too. When a value fails, the result area names the problem instead of showing a number.

有哪些选项可以调整？What options can I adjust?

「由年龄推出生年示意」的设置：「年龄（周岁）」默认 30；「参考日」默认 2026-10-20。每次生成结果都按当前设置处理。Settings in the Date of Birth from Age (Demo) — "Age (years)" default 30; "Reference date" default 2026-10-20. The result always uses the current settings.

时区如何处理？How are time zones handled?

「由年龄推出生年示意」按日历日期计算，只有“今天”取自你设备的本地日期；计算不涉及钟点，所以时区和夏令时不影响结果。The Date of Birth from Age (Demo) works with calendar dates; only "today" comes from your device's local date. No clock times are involved, so time zones and daylight saving time do not affect the result.

「由年龄推出生年示意」免费吗？需要注册吗？Is the Date of Birth from Age (Demo) free? Do I need an account?

「由年龄推出生年示意」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 of Birth from Age (Demo) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.