BUDAPEST (AFP) - Caeleb Dressel brought the curtain down on the world championships with an historic seventh gold medal in Budapest on Sunday (July 30), equalling the record of swim legend Michael Phelps.

Dressel swam the third leg of the men's 4x100m medley relay to leave him with seven golds to equal fellow American Phelps's record from a single worlds set at the 2007 championships in Melbourne.

"I'm very happy to be done, pretty tired," admitted the University of Florida student after winning four golds in 48 hours.

He had become the first swimmer to claim three world golds in one session on Saturday by winning the 50m freestyle, 100m butterfly and mixed 4x100m freestyle titles in a jaw-dropping 98 minute-spell.

"I was seeing a star being born, he's such a great guy, I thought I was witnessing the start of an awesome career," said US backstroker Matt Grevers after witnessing Dressel make history.

Dressel's seven golds include three individual titles in the 50m, 100m freestyle and 100m butterfly, plus relay golds in the 4x100m freestyle, 4x100m mixed freestyle, 4x100m mixed medley and Sunday's 4x100m medley.

His stunning display has earned comparisons with both Phelps and Mark Spitz, who won seven gold medals at the 1972 Olympic Games in Munich.

The performances have been the icing on the cake for the USA, who finished with 38 swimming medals in Budapest - over five times more than nearest rivals Britain, who won seven.

Not to be outdone by the men, the USA broke the world record in winning the women's 4x100m medley relay as Simone Manuel touched the wall at 3:51.55 minutes to break their own record set at the 2012 London Olympics.

Lilly King got the evening off to a bang with a world record in winning the women's 50m breaststroke.

King clocked 29.40 seconds, breaking the four-year-old record, with Russia's Yuliya Efimova taking silver at 0.17 back.

The victory was King's second of week over Efimova, who took bronze in the 100m final but had beaten the American over 200m with a commanding display on Friday when King finished fourth.

Swedish sprint queen Sarah Sjostrom picked up her her third sprint title in Budapest with victory in the women's 50m freestyle final having set the world-record in the semis.

She also won the 50m and 100m butterfly finals and leaves Budapest with two world records after she became the first woman to swim the 100m freestyle under 52 seconds last Sunday.

Hungary's 'Iron Lady' Katinka Hosszu was roared on by the crowd as she won the women's 400m individual medley to complete the IM double.

This is the third straight world championships where Hosszu has won both the 200m and 400m IM title and she is also the world-record holder in both events.

She admitted the crowd carried her home at the end of a punishing week after also racing in the 100m and 200M backstroke, the 200m freestyle and 200m butterfly.

France's backstroke ace Camille Lacourt brought down the curtain on his career as the 32-year-old won the men's 50m gold for the third straight championships before retiring.

America's Chase Kalisz is continuing the legacy of Michael Phelps and Ryan Lochte in the men's 200m and 400m IM after he won Sunday's final over the longer distance.

Kalisz clocked a new championships record time of four minutes, 05.90 seconds in the 400m final to complete the IM double in Budapest.

"Those guys are my idols, just to be behind them is cool for me," said Kalisz in regards to Phelps and Lochte, who won the 400m IM five times between them.

"I don't think that I will ever be on the level of those guys, I think they are just a step above the level that anyone in our sport will ever be.

"For me to continue our tradition of IM - well I grew up with that. I watched those guys and watched them dominate.