The 27-year-old Swede swam six tenths of a second faster than she had previously during the World Championship and hit the wall at a time of 55.46.
I'm really pleased to finish on 55 seconds. The goal was to swim faster for each event, says Louise Hansson in Eurovision Sports' broadcast.
She finished third on the distance in Shanghai and fourth in Incheon, South Korea. Now came the full hit for the Olympic Games finalist this summer.
The victory meant that she also stopped the 21-year-old Finnish swimmer Laura Lahtinen from getting the bonus check of over 100,000 kronor, which goes to the swimmers who manage to take three straight wins in their event during the World Championship.
Lahtinen only became third and Hansson's winning margin to the 17-year-old Japanese second-place finisher Mizuki Hirai was 35 hundredths.
Sara Junevik also swam in the final and finished sixth on 56.99. Junevik doubled and finished fourth on 100 meters freestyle on 52.61, just over half a second from third place.
Louise Hansson's younger sister Sophie missed the podium on 50 meters breaststroke by 19 hundredths and finished fourth on 29.98.
In the men's 50 meters butterfly, the Swiss Noe Ponti improved his own world record already in the heats by 17 hundredths to 21.50.
Kate Douglass, USA, who has set double world records on 200 meters breaststroke, won the overall World Championship, and on the men's side, Olympic champion Leon Marchand, France, won four gold medals in Paris and became the overall winner.
