How to use it 01 Enter the birth date and time. The age cards appear immediately: Age, Total days, Total hours, Next birthday and, when the lunisolar date resolves, Next lunar birthday. 02 Set a target. Type a date and time into Target time; the card shows the event date and a live countdown. A target in the past counts in the same format, followed by ago . 03 Use a preset. New Year, Chinese New Year, Gaokao and National Day chips fill the target field; each chip prints its whole calendar-day distance. 04 Save events and export. Name an event with its time to pin a second countdown, and Export .ics writes the next birthday as a yearly all-day reminder (FREQ=YEARLY). Worked examples Captured with the page clock fixed at 2026-10-07 12:00 UTC+8.
You enter
The panel reads
Birth 1996-12-31 23:30
Age 29 y 9 m 6 d ; Total days 10,872 ; Total hours 260,916 ; Next birthday 85 days — 2026-12-31
Same birth, next lunar birthday
12/29/2026
Target 2026-12-31 23:59
85d 11h 59m 0s
Target 2026-10-06 12:00
1d 0h 0m 0s ago
Preset chips
New Year 86d , Chinese New Year 122d , Gaokao 243d , National Day 359d
Total days and Total hours are not the same measurement scaled. Ten thousand eight hundred seventy-two calendar days would be 260,928 hours at 24 hours a day, yet the Total hours card reads 260,916 — it counts the continuous span from the 23:30 birth clock to the 12:00 read, which falls twelve hours short of whole days. The birthday reminder exported for this birth starts on 20261231 and repeats yearly, so the calendar app owns the reminder from then on.
Limits
What is accepted. A birth date in the future is rejected and shows no cards; a target time in the past counts as ago . The countdown ticks against this device's clock, so a wrong system time shifts every reading.
Presets and decimals. Three preset chips fall on fixed dates, while Chinese New Year follows the lunisolar calendar and moves each year; chips print whole calendar days, the countdown card prints d/h/m/s. What it does not do. It is not a syncing or reminder service, and it does not count workdays. For business-day windows use Date Difference ; to place a birthday on a month grid with its badges, use Calendar . Where it helps Milestone ages Check an exact age on a policy or pension date: the years/months/days card answers "how old on the day" without manual month borrowing, and the lunar card covers lunisolar birthdays that a solar calendar misses.
Launches and renewals Set a target for a contract end or a launch, save it as a named event, and read the remaining span in days, hours, minutes and seconds; the New Year chip gives the same date as a day count when a brief is written in days only.
Privacy The birth date and saved events stay in local storage on this device; nothing is uploaded.
References
IETF, RFC 5545 — Internet Calendaring and Scheduling Core Object Specification , datatracker.ietf.org （访问日期：2026-10-01）— the all-day event and yearly recurrence in the exported reminder.
ISO, ISO 8601-1:2019, Date and time — Representations for information interchange , iso.org （访问日期：2026-10-01）— date and duration notation.
Wikipedia, Chinese calendar （访问日期：2026-10-01）— the lunisolar birthday behind the next-lunar-birthday card.
Wikipedia, Gregorian calendar （访问日期：2026-10-01）— month lengths and the leap rule used when borrowing days.
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Reviewed by CalcX Editorial Team
Updated 2026-10-01