# Lunar dates, solar terms, and festivals in Kopit Cal

> How Kopit Cal shows the Chinese lunar calendar, the 24 solar terms, and traditional festivals offline on your Mac.

- Updated: July 17, 2026
- Reading time: 6 min read
- Audience: Users who want the Chinese lunar calendar and solar terms alongside their Gregorian dates.

## Summary

Kopit Cal renders the Chinese lunar date, the 24 solar terms, and traditional festivals directly on the month view. Everything is computed offline, so it works without a network connection.

## Key takeaways

- Lunar dates (农历) appear under every day in the month view.
- The 24 solar terms (二十四节气) and traditional festivals are labeled on the days they fall.
- All of this is computed offline, so no server or subscription is involved.

### The lunar date on every day

Under each Gregorian day number, Kopit Cal shows the corresponding lunar date, so 廿九 or 初一 sits alongside 7/13. This makes it easy to keep track of the lunar month without opening a separate app or looking anything up.

- Lunar day and month shown compactly under each date.
- Useful for planning around lunar anniversaries and observances.
- No extra taps required; it is always visible in the month view.

### Solar terms and festivals

The 24 solar terms mark the traditional agricultural year, and Kopit Cal labels each one on its day, such as 清明 or 冬至. Traditional festivals like 春节, 端午, and 中秋 are labeled the same way, so the cultural calendar sits right on top of your schedule.

- All 24 solar terms (二十四节气) are placed on the correct days.
- Traditional festivals appear as day labels.
- Cultural dates share the day cell with your events.

### Computed offline

The lunar calendar and solar terms are computed on-device using the Foundation Chinese calendar together with the Shouxing formula for the solar terms. Because the math runs locally, the lunar data is available immediately and does not depend on any network request or account.

- Uses the Foundation Chinese calendar for lunar dates.
- Uses the Shouxing formula for accurate solar terms.
- No connection needed for lunar dates, terms, or festivals.

## FAQ

### Does the lunar calendar work offline?

Yes. Lunar dates, the 24 solar terms, and traditional festivals are all computed on your Mac, so they display without any network connection.

### Where do the lunar dates come from?

They are derived from the Foundation Chinese calendar, with solar terms calculated using the Shouxing formula. Nothing is fetched from a server.

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Canonical page: https://cal.kopit.app/docs/lunar-calendar-and-solar-terms

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