Home › Notes › Solar terms › Haji

Haji (夏至)
— the longest day

Solar terms · 2026.08.27 · 5 min read

Haji is the moment the sun climbs farthest north. After this day, the days start getting shorter again. It sits exactly opposite Dongji, and among the 24 solar terms it's a gi (氣).

How long is the day on Haji?

In Seoul, the sun rises around 5:10 a.m. and sets around 7:56 p.m. That's 14 hours 46 minutes of daylight.

That's 5 hours 12 minutes more than on Dongji. Over six months, the hours of daylight rise and fall by that much.

Haji times by year

Haji is almost fixed on June 21. Only its time shifts about six hours later each year, then comes back in a leap year.

Is Haji the hottest day?

No. Haji is the day the most sunlight comes in, not the hottest day.

Land and sea take time to soak up heat. There's a lag of about a month and a half between when the most heat comes in and when the most has built up. So the actual peak temperatures arrive around Daeseo (大暑, Major Heat; July 22–23). This is called seasonal lag.

Does the Saju month change at Haji?

No. Haji is a gi (氣). The Horse month (午月) begins not at Haji but at Mangjong (芒種, Grain in Ear; June 5–6) and runs until the next Soseo (小暑, Minor Heat; July 6–7). Haji simply marks the midpoint of that Horse month.

I've explained how jeol and gi are divided in The 24 solar terms: a complete guide.

Where does Haji sit in Saju?

O (午) is the peak branch of Fire (火). Of the twelve Earthly Branches, it's where Fire energy gathers most purely, and Haji is its very center. That's why, in Saju, people born in the Horse month are read as having “a thick layer of Fire.”

But here's the interesting part. The point where yang fills to the brim is also where the first trace of yin is born. This is called ireum-sisaeng (一陰始生), and it pairs with Dongji's iryang-sisaeng.

The highest point is also where the descent begins — that's the story Haji and Dongji tell together.

So when reading the Saju of someone born in the Horse month, Fire isn't automatically read as a strength. Dense energy depends on how you use it. You can see which energies run dense or thin in your Eight Characters in Five Elements balance.

Things worth doing around Haji

• Wrap up the first half of the yearIt's late June, a natural halfway point. Pick just one thing you set out to do at the start of the year and check in on it.
• Start preparing for the heat nowThe hottest days are still a month and a half away. Passing Haji doesn't mean you're over the hump — it's only the beginning.
• Set dates for summer plansThings that crowd into peak season — vacations, moves, events — are easier to book early. The Son-eomneun-nal calendar should help.