Mark Kiptoo secured his first international representation for Kenya at the 2007 All-Africa Games, marking the start of a distinguished career in long-distance running. That same year, he showcased his versatility by winning the 5000 metres and earning a silver medal in the 10,000 metres at the 2007 Military World Games. Kiptoo further demonstrated his track prowess with a personal best of 13:12.60 minutes for the 5000 metres in Belgrade. His early career progression included an 18th-place finish at the 2008 World Cross Country Championships and an impressive 7th place at the 2009 World Cross Country Championships.

Most recently, in 2025, he claimed his third consecutive Zürich Marathon title with a time of 2:09:16, a testament to his enduring competitive success in long-distance running.