Nirmal Purja (known as Nims or Nimsdai) MBE (Nepali: निर्मल पुर्जा) is a Nepal-born naturalised British mountaineer and a holder of multiple mountaineering world records. Prior to taking on a career in mountaineering, he served in the British Army with the Brigade of Gurkhas followed by the Special Boat Service (SBS), the special forces unit of the Royal Navy. Purja is notable for having climbed all 14 eight-thousanders (mountain peaks above 8,000 metres or 26,000 feet) in a record time of six months and six days with the aid of bottled oxygen. This was a record at the time of climbing, although it was broken in 2023 by Kristin Harila and Tenjen Sherpa, who summitted all 14 eight-thousanders in 92 days. He was also the first to reach the summits of Mount Everest, Lhotse and Makalu in a time period of 48 hours. In 2021, Purja, along with a team of nine other Nepalese mountaineers, completed the first-ever winter ascent of K2. Purja was the only team member to summit without the use of supplemental oxygen, becoming the first person to do so in winter.