The ITU accepts a 5% margin of error in the cycle and run course distances.[1] Name Swim Bicycle Run Notes Super Sprint 400?m (0.25?mi) 10?km (6.2?mi) 2.5?km (1.5?mi) Distances vary, but this is a standard Super Sprint course. Sprint 750?m (0.5?mi) 20?km (12.4?mi) 5 km (3.1?mi) A 500?m swim is also common. The Sprint Distance is the fastest growing triathlon race distance in the United States Olympic 1.5?km 40?km 10?km Also known as "international distance", "standard course", or "short course". ITU-Long Distance 3.0?km 80?km 20?km Shortened in 2006 Half-Ironman 1.2?mi (1.9?km) 56?mi (90?km) 13.1?mi (21.09?km) Also called an "Ironman 70.3", or "medium distance". Triathlon one 0 one 1.86?mi (3.0?km) 80.6?mi (130?km) 18.6?mi (30?km) Made debut in 2007 Ironman 2.4?mi (3.8?km) 112?mi (180?km) 26.2?mi (42.195?km) marathon Also known as "iron distance" or "long distance".