en.wikipedia.org/wiki/LeetCode

LeetCode's own history page says "2011 年 | LeetCode 起源于美国硅谷" (LeetCode originated in Silicon Valley in 2011) and separately says "2015 年 | 转型为互联网技术人才成长平台" (it transformed into a tech-talent growth platform in 2015). That means 2015 was a later milestone, not the platform's origin year.

Winston Tang also wrote in a July 30, 2024 op-ed that job candidates use "a test prep site I founded 13 years ago." Thirteen years before July 2024 is 2011.

So the article's statement that LeetCode was founded in 2015 is inconsistent with both LeetCode's own timeline and the founder's own account. The page appears to be confusing LeetCode's 2015 transformation/incorporation-era milestone with the platform's actual 2011 origin.

On the page itself, this sentence cites Similarweb's "leetcode.com Traffic analytics, ranking & audience (May 2025)" report. Similarweb's own documentation defines Monthly Visits as the sum of all visits (non-unique) per month. In other words, it counts sessions/visits, not unique people.

Similarweb distinguishes traffic counts from audience counts; its documentation separately describes audience metrics such as Deduplicated Audience for individuals. So turning a Similarweb traffic number into "monthly visitors" is a metric error.