Alonso needed to win the Indian Grand Prix at the Buddh International Circuit on Sunday and hope Vettel finished lower than fifth to keep the fight alive heading to Abu Dhabi next week, but a scrappy first lap ended the Spaniard's hopes as Vettel cantered to victory - his sixth in a row and 10th of the year.
Alonso, the last man who could have denied Vettel a fourth world title, admitted that the championship was destined to go to the German several races ago and felt no strong emotions after finally having it confirmed.
"It's not a surprise," he said. "We knew that Sebastian was becoming champion three or four races ago. It was something you just put inside and the day arrived today. It's no surprise.
"This is a sport. Someone did better than us this year. This was Sebastian and Red Bull, and next year we will try to do better and keep fighting until the end.
"Today is a day to congratulate him and for him to enjoy the championship. It's a day for us to start working even harder because we have a very strong challenge in front of us.
"They [Red Bull] been very strong, dominating F1 for the last four years, so we need to do something better because it's clear that it's not enough.
"We will start immediately and next year we want to win. We have to work."
Alonso's slender title hopes were as good as severed within yards of the start on Sunday as he tagged the back of the second Red Bull of Mark Webber in the first corner before hitting Jenson Button's McLaren further round the lap.
The double contact forced a trip to the pits for a new nose and left his car handling poorly for the rest of the race, which he completed in 11th place.
"After the contact with Webber the race for sure was uphill for us," said Alonso. "It was more difficult with one extra stop and we didn't have the time or the pace to recover the positions. The steering was very heavy to the right and light to the left.
"It was a little bit sad that we lost important points but there was nothing we could do today."