James Magnussen (born 11 April 1991) is an Australian swimmer. He is the current 100-metre freestyle world champion, and holds the 4th fastest swim in history in the 100-metre freestyle with a time of 47.10, which also stands as the fastest swim in textile swimwear material.

He has won a total of seven medals in major international competition, three gold, three silver and one bronze, spanning the Olympics, World Championships, Commonwealth Games, and the Pan Pacific Championships.

2010

At the 2010 Australian Swimming Championships, Magnussen place 3rd in the 100-meter freestyle with a time of 49.43, thus qualifying for the national team.

Magnussen earned a silver medal with Eamon Sullivan, Kyle Richardson, and Cameron Prosser in a time of 3:14.30, finishing behind the United States.[3] Swimming the anchor leg, he had a split of 48.25. In the 100-meter freestyle, Magnussen finished 10th overall with a time of 48.94.

Shortly after the Pan Pacific Swimming Championships, Magnussen competed at the 2010 Commonwealth Games in Delhi. In the 4×100-meter freestyle relay, Magnussen won a gold medal with Kyle Richardson, Eamon Sullivan, and Tommaso D'Orsogna in a time of 3:13.92. At year's end, Magnussen competed at the 2010 FINA World Swimming Championships (25 m) in Dubai, and was part of the Australian team that finished 5th in the 4×100-meter freestyle relay.

2011 World Championships

At the 2011 Australian Swimming Championships, Magnussen qualified for the national team by winning the 100-metre freestyle in a time of 48.29.[6]

At the 2011 World Aquatics Championships, Magnussen won a total of three medals, two golds and one silver. In his first event, the 4×100-meter freestyle relay, Magnussen won gold with Matthew Targett, Matthew Abood, and Eamon Sullivan in a time of 3:11.00. As the lead-off swimmer, he had a with a time of 47.49. Magnussen's lead-off time eclipsed Pieter van den Hoogenband's (unofficial) pre-polyurethane suit record of 47.84, and, at the time, was the fastest swim ever over that distance by a swimmer not wearing the now-banned suit. Four days later, Magnussen became the first Australian man to win the 100-meter freestyle at a World Championships, with a time of 47.63 seconds. At the first 50 in the 100-metre freestyle, Magnussen was in fifth place in 22.94, but came back fastest in 24.69 for the win. After the race, Magnussen said, "When I get back to Australia, I will be relaxing with my friends, and it will sound amazing to be called a world champion. It has been six weeks since I have gotten a good night's sleep. No Australian has won this race at the world championships before, so it is good to be in the same club as the legends of this sport."On the final night of competition, Magnussen won a silver medal in the 4x100-meter medley relay with Hayden Stoeckel, Brenton Rickard, and Geoff Huegill in a time of 3:32.26. Swimming the freestyle leg, Magnussen had a split of 47.00, by far the fastest in the field and was almost enough to overtake the gold winning Americans for 1st place.

2012 Australian Swimming Championships

At the 2012 Australian Swimming Championships, which also served as Australia's Olympic trials, Magnussen qualified for the 2012 Summer Olympics by becoming the national champion in the 50 and 100-meter freestyle. In his first event, the 100-meter freestyle, Magnussen recorded a time of 47.10 to win by over half a second. His 100-meter freestyle time was the 4th fastest swim in the history of the event, and also lowered his own unofficial textile record of 47.49. In the 100-meter freestyle final, Magnussen had a drastic change of tactics compared to his swims in Shanghai. At the first 50, Magnussen had a swift split of 22.68, and came back in 24.42. In the 100-meter freestyle final in Shanghai, he went out in 22.94 and came back in 24.69. Thus, Magnussen was more aggressive in the first 50-meters. Magnussen has stated he does plan on targeting César Cielo's world record of 46.91 in the 100-meter freestyle. After topping the heats (22.19) and semifinals (21.87) in the 50-meter freestyle, Magnussen won the final in a time of 21.74, the fastest any Australian has ever been in textile swimwear in that event. Prior to this meet, Magnussen's personal best in the 50-meter freestyle was 22.41.

2012 Summer Olympics

At the 2012 Summer Olympics in London, Magnussen won a total of two medals, one silver and one bronze. In his first event, the 4×100-meter freestyle, Magnussen and his three other relay team members came fourth behind France, United States and Russia, despite being the favorites. As the lead-off leg, Magnussen recorded a time of 48.03, much slower than the 47.49 he led off last year in Shanghai. In the 100-meter freestyle final, Magnussen came in second by one-hundredth of a second to American swimmer Nathan Adrian 47.53 to 47.52, winning the silver medal. Overall, he said in an interview after his swim he swam his best but unfortunately it wasn't enough. In the 50-meter freestyle, Magnussen failed to advance to the final, finishing with a time of 22.00 in the semifinals. Issues pertaining to Magnussen's behaviour before and during the 2012 London Summer Olympics, became apparent, due to reports Australian Swim Team teammates, ultimately cheered upon Magnussen's defeat in the 100-meter freestyle final.

2013 World Championships

In his first event at the 2013 World Aquatics Championships in Barcelona, Magnussen combined with Cameron McEvoy, Tommaso D'Orsogna, and James Roberts in the 4x100-meter freestyle relay, with the team finishing fourth place, repeating their result from the 2012 Olympics. Swimming the lead-off, Magnussen recorded a split of 48.00, finishing behind American Nathan Adrian for the second-best opening leg. Going into the relay, Magnussen held the top 100-meter freestyle time of 2013 with a 47.53 but like 2012, was not able to replicate his in-season time.

In the 100-meter freestyle, Magnussen successfully defending his title, winning with a time of 47.71.