Digital locks became standard in Korea through apartment living, frequent moves and a growing preference for convenience and security.
Ask a Korean when they last used a house key, and many will pause.
Some will admit they don't remember. Others will say they've never owned one.
In much of the world, a key ring is a basic tool of adulthood — one for the front door, maybe one for a bike lock or a mailbox.
In Korea, that ring has all but disappeared. Enter a code, scan a fingerprint, tap a card: the front door opens with no metal involved.
About 80 percent of Korean households use a digital door lock, compared with 40 percent in Japan, 35 percent in Europe and the Americas and 14 percent in China, according to a report by the Korea Trade-Investment Promotion Agency (Kotra).
Korea's lock industry also says the country was the first to commercialize the technology.
Experts say the reason lies in how Koreans live: mostly in large apartment complexes built to the same specifications, and in a rental market where tenants come and go often.
The keypad on almost every Korean front door traces back to a thief who used copied keys.
While working as a software engineer at Daewoo Electronics' central research lab, Ha Jae-hong read a news story about a woman in her 50s who was arrested after stealing about 500 million won ($372,000) from upscale saunas in Gangnam District, southern Seoul, using copied keys. She had used the money to send her three children abroad to study.
The story gave Ha an idea: a lock whose code changes every time it opens, so that a copied key would be worthless.
He founded a company in 1997 to build it. In 2001, it was renamed iRevo, the maker of the Gateman lock.
In 2004, the industry estimated that about 18 percent of Korean homes had a digital lock and projected that the share would reach 51.4 percent by 2006. Most newly built apartments were already installing them.
The locks were expensive at first, and older rental housing held on to keys for a while.
"Until around 2004, 2005, 2006, a lot of the studio apartments near universities still had keys," said Lee Eun-hyung, a research fellow at the Korea Research Institute for Construction Policy. "Roughly speaking, [digital locks] spread widely from the 2010s, even to ordinary houses."
Prices fell as the locks spread.
"The cheap ones got really cheap — under 100,000 won, some for just tens of thousands of won — so there's no burden in terms of price," Lee said.
Lee also pointed to the Korean temperament.
"We Koreans are a bit impatient, and [we] don't like inconvenience," Lee said. Compared with digging through a bag or pocket for a key, then sticking it in a lock and turning it, a code or a card tap is simply easier.
Even the keypad is starting to go.
Property platform Zigbang's Haven lock, released in 2025, has no number keypad at all — the company says it was the first in Korea to drop it. It opens with face recognition or a phone app, which can also issue temporary passwords.
Housing explains much of it.
Apartments made up 65.8 percent of Korea's 20.18 million homes in 2025, according to the Ministry of Data and Statistics.
"Korean apartments are a highly standardized form of housing that supplies anywhere from several hundred to several thousand units at once with set specifications," said Jung Heon-mok, a professor of anthropology at the Academy of Korean Studies who has studied Korean apartment complexes. "So once a particular fixture is adopted, it can quickly settle in as a kind of 'standard feature.'"
How firmly Koreans now expect a keypad became clear this summer.
In July, Hoban Construction opened a model home for a new apartment complex in Gimpo, Gyeonggi, where residents are scheduled to move in in 2030. A model home is a full-size show unit that Korean builders set up so buyers can see an apartment years before it is built.
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