Lydia Sebastian, 12, has achieved the maximum score in the Mensa IQ test, surpassing physicists Albert Einstein and Stephen Hawking. She scored 162, the maximum score for under-18s. The IQs of both Hawking and Einstein are believed to be 160.

Sebastian is the third student this year to attain the maximum score. In an interview with The Guardian, she said: "At first, I was really nervous but once I started, it was much easier than I expected it to be and then I relaxed." She finished the test with a few minutes to spare.

Her father, Arun Sebastian, a radiologist at Colchester general hospital, said: "Lydia had looked at the websites for the IQ tests herself and had shown an interest in them and talked to my wife about them, so she said: 'Why don't you go ahead with them'?"

Lydia has reportedly read all the seven Harry Potter books thrice. "When she was a few years old she was reading books that were for children several years older than her, " Arun said and added, "Maths is her favourite subject; she won a prize for that when she was at primary school."

Lydia Sebastian, the girl who beat A. Einstein and S. Hawking by achieving a maximum score of 162 on a Mensa IQ test pic.twitter.com/mQCHM81HbK September 3, 2015

Lydia, a student of Colchester County High School in Essex, has played the violin since age four. Her mother, Erika Kottiath, is an associate director at Barclays Bank.

Mensa is the largest and oldest high-IQ society in the world in which membership is open to anyone who can demonstrate an IQ in the top 2% of the population, measured by a recognised or approved IQ testing process, according to The Guardian.