How to work out who’s won Eurovision before it’s announced – using mathematics

As soon as the 2021 Eurovision hosts announced that France had received 251 phone votes, taking the French to a total of 499, this year's competition became a two-horse race. The only country still to have its phone votes announced was Switzerland, who needed at least 258 points to beat Italy to first place.

“Everything is balancing on this pivotal moment,” said host Chantal Janzen. It then took an agonising 102 seconds for the presenters to announce that Switzerland had only received 165 points. Italy had won.

But one man knew exactly who had won as soon as France's points had been declared – 102 seconds before anyone else. He had worked out how to pip the hosts to the post.

Alex Lewis is a property developer and stone skimming champion who lives in Helensburgh, Scotland. This year was the first Eurovision he had ever watched. “I didn't think it would be very good but it was actually really entertaining,” says the 24-year-old, who wants to study economics next year at the University of Glasgow. He points out that, using what he describes as “pretty simple maths”, anyone can work out who the winner is in real time.

If you're not familiar, here is a crash course in how the convoluted Eurovision scoring system works. A country's total points in the final come from two categories: points from a "jury" in each of the voting countries (39 this year); and votes from members of the public who have phoned in. The jury's votes are announced first. The jury (comprising five musical experts from each respective country) only award points to their 10 favourite countries, and they do so by allocating them 12, 10, 8, 7, 6, 5, 4, 3, 2 or 1 points. (Why isn't the system 1-10? No one knows.)

The phone votes are announced after this – but, unlike the jury votes, they are not announced per voting country, the scores from each voting country are simply added together to make a total. Crucially – and here is the problem – this system works in the same way as the jury system, with a country receiving 12 points if, for example, it was the most popular of the top 10 and one point if it was the least popular. (Some countries – like the UK – simply received nul points overall because they didn't even feature in the top 10 in either category.)

In each of the two voting categories there are therefore 2,262 points. Why? Because adding 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 gives you 58, and 39 countries vote. So 58 x 39 = 2,262. When the phone votes are being announced, therefore, all you have to do is start from a total of 2,262 and subtract each country's figure as you hear it being announced.

In this year's competition Lewis was able to work out that once France's total had been declared, 2,097 points had already been used up. Only 165 votes remained. It was impossible for Switzerland to beat Italy. It was impossible for anyone to beat Italy.

Lewis tried it with the 2019 competition as well, and it worked perfectly. “Instantly I knew,” he says. “It's not something that it would take you ages to work out.” But it seemed almost too good to be true. Why would the audience and the contestants not celebrate the result before it was announced? One obstacle is that the calculation is fairly complex, but fans may also have other things on their mind: their own national loyalties; the range of bizarre performances; and the tactical voting that famously occurs.

So far, Lewis hasn't seen anyone online mention this “obvious flaw”. He wondered that if he told the official Eurovision organisation about the flaw, they might try to silence him. He mentioned the discovery to Eurovision-loving friends of his, who said that if enough people knew about this, the organisation would have to change the rules. I emailed the organisation's press department but so far have received no response.

It does seem that the contest might be compromised if word spread about the flaw. As Lewis says, “Anyone in the audience with this [calculation] could basically shout out the result – and funnily enough, I'm planning on going next year...”