Guide
What “(tentative)” means on a holiday calendar
Short answer: the date is an estimate, because the holiday depends on a moon sighting or an official announcement that hasn’t happened yet.
What does (tentative) mean?
The date isn’t confirmed yet
Why some holidays can’t have a fixed date
Most public holidays sit on the Gregorian calendar and never move — Christmas is always 25 December. But a large share of the world’s holidays don’t work that way. Islamic holidays follow the Hijri calendar, whose months begin when the new crescent moon is actuallysighted. Because visibility depends on weather and geography, the exact Gregorian day isn’t known until close to the time, and two countries can legitimately observe the same holiday a day apart.
That’s why calendar feeds — including the ones inside Google Calendar, which is where most people first see the label — publish a computed estimate and mark it(tentative). It isn’t an error, and it isn’t a bug in your phone. It’s the calendar being honest that the date could still shift.
Which holidays usually carry the label
Mostly the Islamic observances: the Prophet’s Birthday (Mawlid / Milad un-Nabi), Eid al-Fitr, Eid al-Adha,Ramadan’s start, Ashura and Isra and Mi’raj. Some Hindu and Buddhist festivals that depend on lunar reckoning are flagged the same way, and so are a few national holidays whose date is set by proclamation each year.
Upcoming holidays currently marked tentative
Taken live from the same calendar feeds your phone uses. Each links to its full page with dates for every year.
| Estimated date | Holiday | Country |
|---|---|---|
| Maulid Nabi Muhammad | 🇮🇩 Indonesia | |
| The Prophet Muhammad's Birthday | 🇲🇾 Malaysia | |
| Milad un-Nabi | 🇮🇳 India | |
| Maulid un-Nabi | 🇵🇭 Philippines | |
| Isra and Mi'raj | 🇲🇾 Malaysia | |
| Lailatul Isra Wal Mi Raj | 🇵🇭 Philippines | |
| Ramadan Start | 🇸🇬 Singapore | |
| First Day of Ramadan | 🇲🇾 Malaysia | |
| Ramadan Start | 🇵🇭 Philippines | |
| Ramadan Start | 🇮🇳 India | |
| Nuzul Al-Quran | 🇲🇾 Malaysia | |
| Ramzan Id | 🇮🇳 India | |
| Hari Raya Puasa | 🇸🇬 Singapore | |
| Hari Raya Puasa | 🇲🇾 Malaysia | |
| Eid al-Fitr | 🇵🇭 Philippines | |
| Hari Raya Puasa Holiday Day 2 | 🇲🇾 Malaysia | |
| Day of Arafat | 🇲🇾 Malaysia | |
| Bakrid | 🇮🇳 India | |
| Hari Raya Haji | 🇸🇬 Singapore | |
| Hari Raya Haji | 🇲🇾 Malaysia | |
| Eid al-Adha | 🇵🇭 Philippines | |
| Hari Raya Haji (Day 2) | 🇲🇾 Malaysia | |
| Eid al-Adha Holiday | 🇵🇭 Philippines | |
| Muharram | 🇲🇾 Malaysia | |
| King's Birthday (Cocos and Keeling Islands) | 🇦🇺 Australia | |
| Amun Jadid | 🇵🇭 Philippines | |
| Muharram/Ashura | 🇮🇳 India |
Frequently asked
What does (tentative) mean next to a holiday?
It means the date is provisional rather than confirmed. The holiday follows a lunar or observation-based calendar, so the exact day depends on a moon sighting or an official announcement that has not happened yet. The calendar shows its best estimate and flags it as tentative so you know it may shift.
Why is the Prophet’s Birthday marked (tentative)?
The Prophet’s Birthday (Mawlid, 12 Rabi al-Awwal) falls on the Islamic lunar calendar. Because each Hijri month begins with the sighting of the new crescent moon, the corresponding Gregorian date cannot be fixed far in advance and is confirmed by religious authorities closer to the time.
How much can a tentative date change?
Usually by one day, occasionally two. Moon sighting depends on local visibility, so neighbouring countries can observe the same holiday on different days.
When does a tentative date become final?
Typically days to a few weeks beforehand, when the relevant authority announces the sighting or publishes the official public-holiday date.
Should I book time off around a tentative date?
Treat it as a strong estimate, not a guarantee. It is fine for planning, but confirm against your government’s official holiday list before booking anything that cannot move.