The judge sentenced him to life in prison, with a minimum term of 43 years.
Osborne had reportedly become radicalised within a matter of weeks by accessing extreme far-right material online and became "obsessed" with Muslims after watching BBC drama Three Girls about the grooming and sexual abuse of young girls in Rochdale.
Unemployed "loner" Osborne had pleaded not guilty, telling London's Woolwich Crown Court that a man called "Dave" was driving at the time.
"You attempted to kill at least a dozen people and succeeded in taking the life of a peaceful man you knew nothing about and had never met", the judge said.
A CCTV still of Darren Osborne at a pub in Wales planning his attack at Finsbury Park.
She previously told the court how she was "struggling not to fall part" under the weight of her grief, with her mother too afraid to go outside and five-year-old son still asking for his grandad.
"I would like to pay tribute to Mr Ali's family and the local community in Finsbury Park, for their tremendous support and understanding with our investigation during what must have been an extremely hard time for them". You allowed your mind to be poisoned by those who claim to be...
His estranged girlfriend, Sarah Andrews, said the "total loner" had become "brainwashed" and "obsessed" with Muslims since watching a TV drama about the Rochdale grooming scandal in May past year, along with two subsequent terror attacks in the UK.
Earlier, in a victim impact statement, the court heard Ms Akhtar describe how her mother is scared to go out alone "in case she is attacked because she is visibly a Muslim who wears a headscarf".
He said: "In my civilian life I have lived overseas 90% of the time, mostly in Middle East, Arabic countries".
"Our father, like the victims of most terrorism, was entirely innocent, which makes his death in this violent way even more hurtful".
After the attack, an eyewitness had said that Osborne showed no regret or no emotion.
During his nine-day trial, Osborne told the court he had wanted to kill senior Labour figures including leader Jeremy Corbyn and London Mayor Sadiq Khan.