Where the dates come from
- International days: the United Nations and its agencies, such as UNESCO and the World Health Organization, set them. We picked the 101 that brands and creators post about most. Each links to its own page, which gives the date, and the UN's full list has every day.
- Holidays: US law for the US holidays, Mother's Day and Father's Day, the UK government for St Patrick's Day and Easter, and the Church of England for Mothering Sunday. Black Friday, Small Business Saturday, Cyber Monday and GivingTuesday follow US Thanksgiving, so their dates are worked out from it.
- Moon-based days: Lunar New Year, Eid al-Fitr, Eid al-Adha, Vesak and Diwali follow the moon, so their dates change every year and can differ by a day from country to country. The dates here are the ones Singapore's government gives for 2027, and each is marked Moon-based. Easter follows the moon too; its date is worked out the way the Western churches do.
What's left out
- Days of remembrance for the victims of war, genocide, terrorism and disasters. They call for care, not a post idea.
- Days about diplomacy, treaties and security, which few brands or creators post about.
- Unofficial “National X Day” lists, which anyone can add to.
- Other moon-based days, such as the start of Ramadan, Holi and Hanukkah. Check them in your own country's calendar.
How to use the days
- Pick a few days that fit what you post about. A post on a day that has nothing to do with your work rarely lands.
- Check the country: some days are one country's, and a moon-based day can move by a day where your audience lives.
- Plan the posts around them with the content calendar planner, and see when your followers are likely online with best time to post.
- In Unisenda, you schedule each post for the day and time you choose, on every network at once.
Questions people ask
How do I add the days to my calendar?
Choose the days, then tap Add to calendar to get one .ics file. On a computer, open Google Calendar's Settings, then Import & export, and choose the file; Outlook and Apple Calendar open it directly. Each day comes in as an all-day event that doesn't mark you as busy.
Why isn't National Pizza Day on the list?
Days like that come from unofficial lists that anyone can add to, so we left them out. Every day here has an official source, linked next to it.
Why can a moon-based day fall on a different date where I am?
Lunar New Year, Eid, Vesak and Diwali follow the moon, and each country sets its own date; for Eid it can depend on when the new moon is seen. The dates here are the ones Singapore's government gives for 2027, so check your own country's calendar before you schedule.
Is anything I choose uploaded or saved?
No. The list is part of the page, and the calendar file is made on your device. Nothing you choose is sent to Unisenda or kept.
Sources
Checked on 1 November 2026. Each international day links to its own page in the list above. Dates can change, so check the source before you rely on one.
- United Nations: List of International Days and Weeks
- US Code: 5 U.S.C. 6103, Holidays
- US Code: 36 U.S.C. 117, Mother's Day
- US Code: 36 U.S.C. 109, Father's Day
- GOV.UK: UK bank holidays
- Ministry of Manpower, Singapore: Public holidays
- Church of England: Mothering Sunday, what are its origins in the Church?
- Britannica: Valentine's Day
- Britannica: Halloween
- Britannica: Black Friday
- Britannica: Cyber Monday
- US Small Business Administration: Observances
- GivingTuesday: Why GivingTuesday matters
- Google Calendar Help: Import events to Google Calendar
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