Date Difference Calculator｜日期差计算器

日期差计算器 | Date Difference Calculator

日期差计算器 Date Difference Calculator

选择两个日期，计算它们之间的总天数、总周数，以及“年＋月＋天”的日历差值。
Pick two dates to calculate the total days, total weeks, and the calendar difference in years, months, and days.

1. 输入日期 · Input Dates
选择时间区间的起点，例如项目开始日、合同生效日或某个纪念日。
Choose the starting date of the period, such as project kickoff, contract effective date, or an anniversary.
选择时间区间的终点，例如项目结束日、合同到期日或今天。
Choose the ending date of the period, such as project completion, contract expiry, or today.
工具默认计算 “不包含结束日”的天数差，并额外给出 “包含结束日” 时的天数，仅供对照。
By default, the tool uses an exclusive end date convention for total days, and also shows the inclusive total days for comparison.
例如：从 1 月 1 日 到 1 月 2 日，不含结束日为 1 天，含结束日为 2 天。
For example: from Jan 1 to Jan 2, there is 1 day exclusively, and 2 days inclusively.
3. 使用说明与小贴士 · How to Use & Tips
  • 1）适用场景 · Use cases：
    计算项目周期、合同期限、还款间隔、试用期、工龄、宝宝年龄、纪念日间隔等。
    Useful for project timelines, contract terms, repayment gaps, probation periods, years of service, baby age, or days between anniversaries.
  • 2）天数差 · Total days：
    「相差天数」默认采用不含结束日的方式，更接近实际跨越的自然日数；同时给出含结束日的天数，方便对照。
    “Total days” is calculated using an exclusive end date convention, which reflects the span of days crossed; the inclusive value is also shown for comparison.
  • 3）周数差 · Total weeks：
    周数采用「天数 ÷ 7」的方式，并显示“完整周＋剩余天数”，例如 2 周 3 天。
    Weeks are computed as “days ÷ 7”, along with a breakdown into full weeks plus remaining days.
  • 4）年＋月＋天 · Years + Months + Days：
    按日历法，从较早日期逐步推算到较晚日期，例如「3 年 2 个月 5 天」。
    A calendar method is used: starting from the earlier date and adding years, months, and days to reach the later date, e.g., “3 years 2 months 5 days”.
  • 5）顺序自动识别 · Automatic ordering：
    若起始日期晚于结束日期，工具会自动调换顺序，并提示「已自动按时间先后调整」。
    If the start date is later than the end date, the tool automatically swaps them and shows a note about the adjustment.

说明：本工具基于公历日期进行计算，忽略时区与夏令时差异，结果仅供学习、规划与估算参考， 不构成任何法律、财务或投资建议。
Note: This tool uses Gregorian calendar dates and ignores time zones and daylight saving time. The results are for education, planning, and estimation only, and do not constitute legal, financial, or investment advice.