You're standing in the kitchen. Your hands are covered in flour or maybe you're just too lazy to look at the calendar on the wall. You shout across the room, "Hey Siri, how many days are in May?"
It's a simple question. A basic one. Yet, thousands of us ask it every single month. Why? Because the Gregorian calendar is a bit of a mess, and our brains are tired.
The Quick Answer You Came For
If you just need the number right now: May has 31 days.
It always has 31 days. It doesn't pull a "February" and change every few years. It's one of the long ones. Specifically, it is the third month of the year to have 31 days, following January and March.
Why Siri is Your Best Friend for Calendar Math
Siri handles these queries through a mix of its internal "Knowledge Graph" and basic calendar data. When you ask, "Hey Siri, how many days are in May?" the assistant doesn't actually have to "think." It pulls from a static data set.
However, things get interesting when you ask for more than just a number. Siri is surprisingly good at "relative" date math.
- "Hey Siri, how many days until May 1st?"
- "Hey Siri, what day of the week is May 24th?"
- "Hey Siri, how many business days are left in May?"
That last one is where people often get tripped up. While the month has 31 calendar days, the number of working days changes every year depending on where the weekends land and when Memorial Day falls in the United States.
The "Wolfram Alpha" Connection
Historically, Siri used to offload a lot of its math and "fact" queries to Wolfram Alpha. If you've ever seen a weirdly detailed graph or a massive block of data in response to a simple question, that was likely the culprit. Nowadays, Apple handles most of this "first-party" knowledge internally to make the response faster.
The "Thirty Days Hath September" Struggle
Most of us learned the rhyme in grade school. You know the one:
Thirty days hath September,
April, June, and November.
All the rest have thirty-one...
It sounds easy. It’s a catchy little earworm. But in the heat of the moment, when you’re trying to book a flight or plan a project deadline, the rhyme fails. You get to "All the rest" and your brain freezes. Is May in the first group? No. Is it the second? Probably.
This is exactly why voice assistants like Siri, Alexa, and Google Assistant have become our external hard drives for "useless" but necessary info. We’ve outsourced the rhyme to the cloud.
A Quick Cheat Sheet for May Dates
May isn't just a random 31-day block. It's packed. In 2026, the calendar looks a specific way, and knowing the "big" days helps you realize why you're asking Siri for the date in the first place.
Major May Events:
- May 1: May Day (and International Workers' Day).
- May 4: Star Wars Day ("May the Fourth be with you").
- May 5: Cinco de Mayo.
- May 10: Mother's Day (in 2026).
- May 25: Memorial Day (U.S. - Observed).
Honestly, the reason most of us are asking Siri about May's length is because we're trying to figure out if we have an extra day of vacation or if a bill is due on the 30th or the 31st.
The History of Why May Has 31 Days
It wasn't always this way. If you went back to the original Roman calendar (the one Romulus supposedly dreamt up), May was actually the third month of the year. Back then, the year started in March.
May has pretty much always been "long." It was named after Maia, the Greek goddess of fertility and growth. Romans viewed May as a month of "elders" (Maiores), while June was for "youth" (Iuniores).
Eventually, Julius Caesar came along and messed with everything to create the Julian calendar, and then Pope Gregory XIII refined it further in 1582 because the seasons were drifting. Through all that shuffling, May kept its 31 days. It’s one of the most stable months in history.
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Common Siri Misunderstandings
Sometimes Siri gets it wrong. Not the "31 days" part, but the context.
If you ask "How many days in May?" while it is currently May 15th, Siri might occasionally interpret that as "How many days are left in May?"
If you get a weird answer like "There are 16 days remaining," you've hit a context bug. The best way to fix this is to be specific. Ask, "How many days are in the month of May?"
Actionable Tips for Managing Your May Calendar
Since you now know May is a 31-day marathon, here is how to handle it like a pro:
- Check the "Leap" Confusion: Remember that May never changes. Unlike February, you don't need to check the year to know the day count.
- Use Siri for Countdowns: If you're planning a May wedding or event, ask Siri: "How many days until May 20th?" It's faster than counting squares on a screen.
- Schedule the 31st: Many people forget the 31st exists when setting "end of month" reminders. Manually set your recurring reminders for the "last day of the month" rather than a specific number to avoid missing May 31st.
- Confirm the Year: If you are looking at a calendar for a different year, ask "Siri, what day of the week is May 1st, 2027?" to avoid planning errors.
May is the bridge to summer. It’s 31 days of transition. Whether you’re asking Siri because of a bet, a project, or just pure curiosity, you’ve got a full 744 hours to get through the month.
Next Steps:
Go ahead and try a more complex query. Ask Siri, "How many business days are in May 2026?" to see how it handles your specific regional holidays. You can also ask it to "Add an event for the last day of May" to ensure you're utilizing that 31st day to its full potential.