Based on Birth Years, Ki Hee-hyun and Lee Sang-yoon Are 1 Years Apart
Is the age gap between Ki Hee-hyun and Lee Sang-yoon 1 years or 2 years? Why their international ages differ as of September 2026# Is the age gap between Ki Hee-hyun and Lee Sang-yoon 1 years or 2 years? Why their international ages differ as of September 2026
Ki Hee-hyun and Lee Sang-yoon are 1 years apart based on their birth years, but as of 2026-09-17, Ki Hee-hyun is 31 years old and Lee Sang-yoon is 29 years old under the international age system. This makes their current numerical age difference appear to be 2 years. The discrepancy arises because Lee Sang-yoon has not yet celebrated his birthday in 2026.
Following the public confirmation of their relationship, some news reports have described them as being '1 years apart,' while others have said '2 years apart.' This can be confusing, but neither description is necessarily incorrect. The key is to distinguish the difference between their birth years from their international ages on a specific date.
Based on Birth Years, Ki Hee-hyun and Lee Sang-yoon Are 1 Years Apart
Ki Hee-hyun was born in 1995, while Lee Sang-yoon was born in 1996. Comparing their birth years gives 1996-1995=1, making them a couple in which Ki Hee-hyun is the older partner. Several reports about their relationship have likewise described them as an older-woman, younger-man couple with an 1-year age gap.
In short, the birth-year comparison is straightforward.
| Category | Ki Hee-hyun | Lee Sang-yoon |
|---|---|---|
| Birth year | 1995 | 1996 |
| Difference in birth years | 1 years | |
| Older or younger | Older | Younger |
Therefore, if someone asks when Ki Hee-hyun and Lee Sang-yoon were born or how many years apart they are, the clearest answer is that they were born in 1995 and 1996, respectively, and their birth years are 1 years apart.
Why Are Their Current Ages Listed as 31 and 29?
Under the international age system, age is not determined simply by subtracting birth years. You must also check whether each person's birthday has already occurred during the current year.
Ki Hee-hyun's birthday is confirmed as 1995-06-16, and her birthday for the year had already passed by 2026-09-17. She is therefore 31 years old under the international age system.
Lee Sang-yoon's publicly available profile lists his birth date as 1996-09-20. As 2026-09-17 falls three days before his birthday, he is still 29 years old.
Accordingly, their ages as of 2026-09-17 are as follows.
Ki Hee-hyun: 31 years old; Lee Sang-yoon: 29 years old
Comparing only their current international ages gives a 2-year difference.
After September 20, Their International Ages Will Also Be 1 Years Apart
The situation changes once Lee Sang-yoon celebrates his birthday in 2026.
After September 20, Lee Sang-yoon will be 30 years old. Compared with Ki Hee-hyun, who is 31 years old, their numerical international-age difference will also be 1 years.
The following table makes the difference easier to understand by reference date.
| Basis of comparison | Ki Hee-hyun | Lee Sang-yoon | Numerical difference |
|---|---|---|---|
| Birth year | Born in 1995 | Born in 1996 | 1 years |
| International age as of 2026-09-17 | 31 years old | 29 years old | 2 years |
| After Lee Sang-yoon's birthday in 2026 | 31 years old | 30 years old | 1 years |
The main reason both '1 years apart' and '2 years apart' can appear in reports is that their birthdays fall on different dates, and Lee Sang-yoon's birthday is in September.
Why News Reports Alternate Between 1-Year and 2-Year Age Gaps
Reports about their relationship have not used a consistent description.
NewsEn and Hankook Ilbo, among other outlets, identified Ki Hee-hyun as born in 1995 and Lee Sang-yoon as born in 1996, describing them as an older-woman, younger-man couple with an 1-year age gap.
Other reports, however, have described the couple as being 2 years apart.
Rather than relying solely on a news article's stated age gap, it is more accurate to check both individuals' birth years and the reference date.
In particular, when two people have different birthdays, there can be a period during the year when the numerical difference between their international ages is one year greater than the difference between their birth years.
How Should You Remember Their Age Gap as of September 2026?
The least confusing way to describe the couple is: 'Ki Hee-hyun was born in 1995, and Lee Sang-yoon was born in 1996, so their birth years are 1 years apart.'
However, when their international ages are calculated individually before Lee Sang-yoon's birthday, as on 2026-09-17, Ki Hee-hyun is 31 years old and Lee Sang-yoon is 29 years old, producing a numerical difference of 2 years.
Therefore, if you have recently seen articles describing the couple as either '1 years apart' or '2 years apart,' those reports are not necessarily referring to different couples or conflicting personal information. First check whether the comparison is based on birth years or current international ages.
Related Articles
Is Yoon Bo-mi Older Than Jung Eun-ji? Both Were Born in 1993, but Their Birthdays Are 5 Days Apart