Nasen Saadi, 20, from Croydon, fatally stabbed personal trainer Amie Gray, 34, 10 times as she sat beside a fire on Durley Chine Beach in Dorset on the evening of 24 May.
Her friend Leanne Miles, who was sitting next to her on the beach, suffered 20 knife injuries but survived the attack.
Saadi was found guilty after a trial at Winchester Crown Court, which heard how Saadi, who was studying criminology at Greenwich University in London, was asked by one of his lecturers: “You’re not planning a murder, are you?”
He had asked teachers questions about self-defence for murder and how long DNA stays behind.
Saadi told detectives he had an interest in true crime, unsolved cases and horror movies.
During the trial the jury was shown CCTV footage the prosecution said showed Saadi walking along the beach promenade.
They also heard a CCTV audio recording of screaming and a male voice at around 11.39pm – the time of the attack.
A recording of a 999 call made by Ms Miles was played to the court in which she was heard crying in pain.
The 39-year-old told the operator: “I have been stabbed loads of times. Oh my God, I am getting dizzy, please hurry up, please hurry up.”
She continues: “I am bleeding everywhere, I have been stabbed loads of times.”
The defendant, who chose not to give evidence, admitted visiting Bournemouth but denied the offences.
He told police he might have “blacked out” and had no memory of the period that included the attacks.
In a police interview shown in court, Saadi said: “I am not responsible and I have no reason to attack someone for no reason.”
Saadi pleaded guilty to failing to provide his mobile phone code to police.
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