Half marathon

A half marathon is a road running event of 21.0975 kilometres (13 miles 192.5 yards)—half the distance of a marathon. It is common for a half marathon event to be held concurrently with a marathon or a 5K race, using almost the same course with a late start, an early finish, or shortcuts. If finisher medals are awarded, the medal or ribbon may differ from those for the full marathon. The half marathon is also known as a 21K, 21.1K, or 13.1 miles, although these values are rounded and not formally correct.

A half marathon world record is officially recognised by World Athletics. The men's world record time, pending ratification, is 56:42, set by Jacob Kiplimo of Uganda in February 2025 in Barcelona, Spain. The women's world record, in a mixed-gender race, is 1:02:52, set by Letesenbet Gidey of Ethiopia in October 2021 in Valencia, Spain. In a female-only race, the women's world record is 1:05:16, set by Peres Jepchirchir of Kenya in October 2020.

Participation in half marathons has grown steadily since 2003, partly because it is a challenging distance, but does not require the same level of training that a marathon does. In 2008, Running USA reported that the half marathon is the fastest-growing type of race.