April 1:
- APRIL FOOLS
- Ramadan Begins (2022)
- National Sourdough Bread Day - US
- National Day - San Marino
- Republic Day - Iran
April 2:
- World Autism Day
- International Pillow Fight Day (2022)
- National Ferret Day - US
- National Peanut Butter & Jelly Day - US
- Malvinas Day - Argentina
April 3:
- Geologists Day (2022)
- National Chocolate Mousse Day
- National Find A Rainbow Day
April 4:
- International Day for Landmine Awareness
- World Rat Day (aka Every New Yorker's Favorite Animal Day)
- Victims of Violence Holy Day
- National Cordon Bleu Day
- Liberation Day - Hungary
- National Day - Senegal
April 5:
- Arbor Day - South Korea
- International Carrot Day
- Cold Food Festival (2022) - US
- National Deep Dish Pizza Day - US
April 6:
- World Table Tennis Day
- California Poppy Day
- Chakri Day - Thailand
- Fête of the Little Boats - France
- Uprising Day - Sudan
- Bohring-Opitz Syndrome Awareness Day
- National Carbonara Day
- International Day of Sport for Development and Peace
April 7:
- World Health Day
- International Day of Reflection on the 1994 Genocide in Rwanda
- International Beaver Day
- Women's Day - Mozambique
- National Coffee Cake Day
- No Housework Day
April 8:
- World Pageant Day
- National Empanada Day
April 9:
- National ASMR Day
- Martyr's Day - Tunisia
- National Chinese Almond Cookie Day
- Unicorn Day
April 10:
- International Safety Pin Day
- World Homeopathy Day
- National Farm Animals Day
- National Siblings Day
April 11:
- International Louie Louie Day
- World Parkinson's Day
- Heroes Day - Costa Rica
- Liberation Day - Uganda
- National Ranch Water Day
- Submarine Day
April 12:
- Look Up At The Sky Day
- International Day of Street Children
- International Day for Human Space Flight
- Grilled Cheese Sandwich Day
April 13:
- National Peach Cobbler Day
- National Day - Chad
- Cambodian New Year - Cambodia
- International FND Awareness Day
- World Sarcoidosis Awareness Day
April 14:
- Dolphin Day
- International Moment of Laughter Day
- World Chagas Disease Day
- Fast and Prayer Day - Liberia
- Pan American Day - Honduras
- Thingyan (Burmese New Year) - Myanmar
April 15:
- World Art Day
- First Day of Passover (2022)
- National Day - Niger
- Day of the Sun - North Korea
- Rubber Eraser Day
April 16:
- World Voice Day
- Independence Day - Cyprus
- New Years Day - Myanmar
- National Orchid Day
April 17:
- International Bat Appreciation Day
- World Hemophilia Day
- Independence Day - Cambodia
- National Day - Syria
- International Haiku Poetry Day
April 18:
- International Day for Monuments and Sites
- International Amateur Radio Day
- Independence Day - Zimbabwe
- National Transgender HIV Testing Day
- Piñata Day
April 19:
- Independence Day: Venezuela
- Patriots' Day: Uruguay
- Republic Day: Sierra Leone
- National Garlic Day
- Primrose Day
April 20:
- Chinese Language Day
- Volunteer Recognition Day – (Canada and the United Kingdom)
- National Cheddar Fries Day
- National Lookalike Day
April 21:
- British National Tea Day
April 22:
- International Mother Earth Day
- International Girls In ICT Day
- National Jelly Bean Day
April 23:
- English Language Day
- Spanish Language Day
- World Book and Copyright Day
- World Laboratory Day
- International Pixel-Stained Technopeasant Day
April 24:
- Fashion Revolution Day
- World Meningitis Day
- World Veterinary Day (2022)
April 25:
- World Penguin Day
- Parental Alienation Day
- World Malaria Day
- ANZAC Day - Australia, New Zealand
- Liberation Day - Italy, Portugal
- National Flag Day - Swaziland
- Sinai Liberation Day - Egypt
April 26:
- World Intellectual Property Day
- International Chernobyl Remembrance Day
- Union Day - Tanzania
April 27:
- International Guide Dog Day (2022)
- Independence Day - Afghanistan, Sierra Leone, Togo
- World Tapir Day
- Tanner's birthday
April 28:
- World Day for Safety and Health at Work
- Global Pay It Forward Day
- National Blueberry Pie Day
April 29:
- International Dance Day
- World Wish Day
- Denim Day
April 30:
- International Jazz Day
- World Tai Chi and Qigong Day (2022)
- International Sculpture Day (2022)
- Fall of Saigon - United States of America
- Independence Day - Israel
- Vappu Day - Finland
- National Bubble Tea Day