Finnish international airline Finnair has been asking passengers to step on a set of scales before boarding flights in Helsinki in an effort to work out better average weights for the airline's calculations.

The weight of the entire aircraft, including the passengers, goes into calculating how much fuel the plane will need, meaning better numbers could help Finnair work out their top fuel efficiency.

According to reports, Finnair has said that passenger weights will not figure into ticketing costs. Across 31 October and 1 November, 180 passengers had agreed to step on the scales before their flights, the airline said. They're aiming to weigh 2,000.

"We found yesterday and today we had people of all shapes and sizes," Finnair communications director Päivyt Tallqvist told the BBC. "We had Finnish and Asian customers, we had a variety of male and female and of different sizes."

The airline had up until now been using European Aviation Safety Agency estimates of passenger weights, but Finnair thinks their average might be different, noting that weights of passengers and their luggage fluctuates between seasons.

After gathering the weights of 2,000 passengers in this round, the airline plans to repeat the process in spring to see the seasonal differences that could prove useful for weight calculations. The passengers weighed took part voluntarily and anonymously.

Some on social media were unconvinced by Finnair, saying the move was a step toward charging heavier passengers more. "Will they eventuall[y] charge more for overwright passengers? I think so." one user wrote.

In an opinion piece for the Metro, writer Marianda Larbi said that asking to be weighed could be humiliating for some. "One has to wonder what psychological effect being weighed in public will have on people who already struggle with body image and eating disorders," she wrote.