how often are athletics world championships

The World Athletics Championships are held every two years (biennially). Initially, the championships were held every four years when they started in 1983, but since 1991 they have taken place every two years in odd-numbered years to avoid clashing with the Olympic Games, which are held every four years in even years. For example, the 20th edition is scheduled for 2025 in Tokyo, and the next one in 2027 in Beijing.