At the 2024 World Aquatics Championships in Doha, Qatar, he broke the 26-second barrier in the 50m backstroke, achieving a global ranking of 22nd,[6] 3rd in Asia, and 1st in South Asia—a milestone for Sri Lankan swimming.

[10] With over 700 medals and 82 national age group records, Peiris continues to be a dominant and inspiring figure in Sri Lanka sports.

Peiris competed in the Asian Schools Games in Indonesia, where he won silver medals in both the 50m butterfly and 50m backstroke events,[4] showcasing his skill and earning recognition on the school-level international stage.

Peiris competed at the International Sports Games, also known as the Mini Olympics, held in Russia, where he achieved a world rank of 1st in the 100m backstroke,[11] marking a significant milestone in his swimming career on the global stage.

Peiris represented Sri Lanka at the Youth Commonwealth Games in the Bahamas, where he placed in the top 5 for the 50m butterfly 50m backstroke events.

[12] Peiris qualified to represent Sri Lanka at the 2018 Asian Games in Jakarta, Indonesia, an opportunity that coincided with his Advanced Level (A/L) exams.

At the 2022 Commonwealth Games in Birmingham, Peiris continued his record-breaking performances, setting a new national record in the 50m backstroke and achieving a seasonal best in the 50m butterfly,[19] highlighting his steady progress.

[20] Peiris competed in the Asian Games, Hangzhou, China, where he placed 10th in Asia in the 50m backstroke (short course),[21] showcasing his competitive standing in the region.