What Temperature Will Seoul Actually Be on My Travel Dates? Six Years of Real Data, Plus Sunset Times
Search “Seoul October weather” and you get averages. But an average year never actually happened.
The calculator below takes your travel dates and shows you what the temperature in Seoul actually was on those days — year by year, from 2020 to 2025. It also calculates the sunset time for each date. What you do with the numbers is up to you.
Why averages are useless
| Date | Year-by-year highs (2020→2025) | Spread |
|---|---|---|
| 24 January | 6.9° · 10.9° · 7.5° · −8.9° · −4.3° · 7.4° | 19.8 degrees |
| 2 August | 26.3° · 28.2° · 29.4° · 31.0° · 30.1° · 36.3° | 10.0 degrees |
On 24 January — the day with the widest year-to-year swing in the entire calendar — some years felt like early spring, and one year hit nearly minus nine. Take the average and that spread disappears entirely.
Temperatures are from Open-Meteo ERA5 reanalysis data for Seoul, 2020–2025 (°C). Feels-like temperature may differ. Sunset times are calculated for Seoul coordinates (37.57°N, 126.98°E). Check the daily forecast separately.
What the numbers tell you
(This section is editorial commentary — not calculator output. You do not have to agree.)
1. The 20–25°C sweet spot comes in two chunks
| Window | Length |
|---|---|
| 11 May – 5 June | 26 days |
| 19 September – 5 October | 17 days |
The spring window is over a week longer than the autumn one.
2. Only nine days a year have an average high above 31°C
They cluster in the last week of July (25–31 July), with only two outliers: 4 August and 20 August. “August is hot” is less accurate than “the last week of July.”
3. Sunset varies by two hours and forty minutes
21 December: 17:17. 21 June: 19:57. Across 366 days, sunset falls before 18:30 on 167 days (about 46%). Since most rental shops close around 19:00, this number matters directly when planning evening photos — in winter, it is already dark before you need to return the hanbok.
Hanbok is not seasonal clothing — it is a thin layer
Separate from the numbers, here are two things I observed behind the counter for ten years.
- Summer: A petticoat adds an extra layer beneath the skirt. At the same temperature, hanbok feels warmer than everyday clothes. The jeogori breathes well but has long sleeves.
- Winter: Hanbok itself provides almost no insulation. When layering underneath, remember one thing — the jeogori collar opens in a V shape, so a crew-neck inner will be clearly visible below the neckline. Choose a U-neck or V-neck. Match the colour to the jeogori to be safe.
For today’s weather
→ See the live Seoul street cam and seasonal hanbok guide. This article is for “my travel dates.” That article is for “right now.”
I ran a hanbok rental shop at Gyeongbokgung from 2015 to 2025. Every autumn, customers would arrive in coats they did not need, and every spring, someone would show up in a t-shirt on a day that turned out to be ten degrees. The calculator above is what I wish I had at the counter — not a forecast, just a clear record of what actually happened, year by year, so you can make your own call.
Frequently asked questions
How can I check the actual temperature for my Seoul travel dates?
Use the calculator on this page. Enter a date and it shows the actual high and low temperatures in Seoul for each year from 2020 to 2025, side by side — not a single average, but six years of real recorded data so you can see how much variation there is. For example, on 24 January, the high ranged from 6.9°C in 2020 to −8.9°C in 2023 — a spread of 19.8 degrees.
When is the most comfortable season in Seoul, temperature-wise?
Based on 2020–2025 recorded data across all 366 calendar days, the two windows where the average high sits between 20°C and 25°C are 11 May–5 June (26 days) and 19 September–5 October (17 days). The spring window is over a week longer than the autumn one. Conversely, days with an average high above 31°C number only nine in the entire year, concentrated in the last week of July.
How much does sunset time vary across the year in Seoul?
Sunset on 21 December is around 17:17; on 21 June it is around 19:57 — a difference of two hours and forty minutes. Sunset falls before 18:30 on 167 days (about 46% of the year). Since most hanbok rental shops close around 19:00, winter means the sky is already dark before you need to return the clothes, while in summer it is still broad daylight.
What should I wear under hanbok in winter?
Thermal inners work well, but check the neckline. The jeogori has a V-shaped overlapping collar, so a crew-neck inner will be visible below the collar line. Choose a U-neck or V-neck instead, and pick a colour close to the jeogori to be safe. Some shops rent padded vests (baeja) or outer coats (durumagi) as paid extras.
Shops this applies to
- Haewadal Hanbok (해와달한복)Right by Gyeongbokgung Stn. (Line 3) · short walk to the palacefrom₩9,900Standard · Royal (court) · Themed
- Queens Hanbok (퀸즈한복)Near Gyeongbokgung Stn. (Line 3) · short walk to the palacefrom₩10,000Standard · Premium · Mens
- Gowoonsol Hanbok (고운솔한복)Near Gyeongbokgung Stn. (Line 3) · short walk to the palacefrom₩10,000Standard · Premium · Royal (court)
Prices and free extras are the shops’ own published figures. No paid rankings.