The 2019 exit poll has predicted a whopping 86-seat majority for Conservatives.

The prediction has just been revealed with Boris Johnson on course to win a majority with 368 seats, followed by the Labour Party (191 seats), SNP (55 seats), Lib Dem (13), Plaid Cymru (3), Green (1), Brexit (0) and other parties (19).

But these figures pose as a simple prediction, the final results will be known at the end of the night.

The exit poll is a survey of thousands of voters just after they have cast their ballot.

It is based on 144 constituencies in England, Scotland and Wales, covering both rural and urban seats to offer a balanced and accurate prospect.

The same constituencies are surveyed from one election to the next, for consistency.

This year’s poll is commissioned by BBC News, ITV News and Sky News.

The results were released just after voting closed at 10pm.

Exit pollsters base themselves at a selected polling station in a chosen constituency.

Voters emerging from the polling station are waylaid at regular intervals – every 10th voter, for example – by these fieldworkers, employed by polling specialists Ipsos Mori.

They are given a replica ballot paper and asked to fill it in without anyone watching.

Voters then drop the replica paper into a box that will be opened later.

They do not have to say out loud who they voted for – the main purpose is to increase the accuracy of the results, says Stephen Fisher, associate professor of political sociology at the University of Oxford.

The results are analysed at a secret location in London, by a team of experts.

Even if the 2015 exit poll was more accurate than the opinion polls during the campaign, it did not predict a Conservative majority.

In 2017, the first take of the exit poll correctly predicted the Conservatives would be the largest party, but stopped short of saying there would be a hung Parliament.

The outcome of the exit poll has been becoming more accurate in the past years, as the methodology improved. A valid exit poll has to come within 15 seats of the final outcome, professor Fisher adds.

One of the worst backfires was in 1992, when two separate exit polls, for the BBC and ITN, both predicted a hung Parliament.

nstead, John Major’s Conservative government at the time held its position, albeit with a significantly reduced majority.

The first result from this year’s exit poll will not cover the last half hour of voting. If there’s a late rush of voters that could significantly influence the final result, the exit poll could be updated with a new headline after about 11pm.