1. Longest running group without any member changes
Shinhwa has been going strong since their debut 19 years ago in 1998. They will probably keep this title forever, as the men are still releasing albums and almost every other group has had member changes or have broken up. Because they've been out for so long, they also hold the record for the boy group with the most number of full albums released.
2. Youngest idol to debut
When Samuel Kim debuted in 2015 as a member of '1PUNCH', he was only 13 years old. (He was born in 2002). In fact, Sam is so young that he was one of the youngest members of 'Produce 101', even two years after he debuted.
3. Oldest idol to debut
g.o.d debuted in 1999, and Park Joon Hyung, born in 1969, was a whopping 30 years old when he debuted. Just goes to show age doesn't matter, as he's still well-loved as an entertainer in Korea today.
4. Shortest time to #1 on mainstream music show
WINNER debuted with 'Empty' and 'Color Ring' on August 12th, 2014 (August 14th for a physical album). Just ten days after on 'Music Bank' on August 22nd, the boys took home their first #1 trophy from a mainstream music show. In fact, if you count the cable channel show 'M! Countdown', they won it in even shorter time on August 21st.
5. Longest time to #1 on mainstream music show
BTOB won KBS' 'Music Bank' on April 8th, 2016 with "Remember That", a whopping 1480 days since their debut on March 21st, 2012. BTOB currently holds the title for longest time taken to a #1 on a mainstream music show, and it's not a record that'll be beaten anytime soon. (The boys' first win was on 'Show Champion' with "Way Back Home" on October 21st, 2015, 1310 days after their debut. Even counting cable shows, the boys still took a very long time getting to #1.)
6. Most-watched debut MV on YouTube
At 66 million views, NU'EST beats out all other boy groups as the most-watched boy group debut MV of all time. Most of the views were thanks to their recent appearance on 'Produce 101' when views suddenly spiked because of increased interest. There's no denying that "Face", featuring some Seventeen members, is a classic must-watch.
7. Most-watched MV of all time on YouTube
At 310 million views, Big Bang's "Fantastic Baby" is the most-watched K-pop video of all-time (not counting Psy, who is not in a boy group). The MV is a must-watch for any K-pop fans, featuring the usual dancing, abs, amazing hairstyles, and flashy visuals.
8. Longest #1 on Melon's real-time chart without dropping
It's no surprise that Wanna One, the top 11 boys of 'Produce 101', holds a lot of records - and the most impressive one is their title song's long #1 streak on MelOn. The song stayed at #1 for 210 hours on the real-time chart, the longest ever not just for boy groups. This is NOT the total time #1, but the number of #1 maintained without dropping from the #1 place even once.
9. Most non-Korean members
Not counting Super Junior-M, which is a China-only unit, and EXO, whose non-Korean members have mostly left, GOT7 is the group with the most non-Korean members. In fact, with 3 out of 7 not being Korean, almost half of the group is non-Korean. BamBam is Thai, Jackson is Chinese, and Mark is Taiwanese (technically, Mark is Taiwanese-American), meaning GOT7 is also the most diverse K-pop boy group out there.
10. Shortest idol
Seventeen's Woozi, at a profile height of 164cm (5'5"), is the shortest male idol to have debuted. No matter, because he's a fluffball of total cuteness and a load of talent, and fans love him just the way he is.
11. Tallest idol
It's no surprise that the title of the tallest idol goes to the group named for their tall height. KNK's Seungjun is currently the tallest idol at 190 cm (6'3"). KNK towers over most of the idols out there and Seungjun towers over even KNK.
12. Shortest trainee period
Super Junior's Kyuhyun trained for only 3 months before joining Super Junior. He is one of the best vocalists in K-pop even with his little training.
13. Longest trainee period
G-Dragon started super young, and he trained for 5 years in SM Entertainment before moving to YG Entertainment and training 6 years there. The 11 years of training gave birth to one of Korea's biggest superstars, so it seems like it was all worth it.
14. Most followed on SNS
With 14.6 million followers on Instagram, G-Dragon is not only the most followed male idol - he's the most followed K-pop star, period.
15. Highest ranking on Billboard 200
BTS ranks high above any other male K-pop idol (or any other idol in general) as they landed at #26 on Billboard's main chart Billboard 200 with their 2nd album 'WINGS'. They're also the only K-pop group to be on the chart for 2 weeks with the same album.
16. Most number of first-week album sales
It's hard to compare total sales for idols, as some have more than others. However, what you CAN compare are first-week sales. With over 600,000 copies sold in the first week, EXO's 'The War' takes the title for highest first-week album sales. Additionally, as quadruple million-sellers, there's no one that comes even close to EXO's sales records. The boys recorded over a million albums sold with every single full album, and becoming the first group in 12 years to sell 1 million copies of a single album in 2013.