The claim: Jeremy Corbyn had youth on his side.

Reality Check verdict: If the YouGov and Ipsos Mori polls are accurate there was a big swing of young people to Labour and a considerable increase in their turnout.

YouGov released the first big poll of how different groups voted at the general election on 13 June - the version from Ipsos Mori came out on 20 June. Both of these are estimates based on polling. There are no official figures because the general election is a secret ballot - the closest we have is the British Election Study, but that will not be released for months.

YouGov estimated that voters aged between 18 and 29 preferred Labour to the Conservatives by 63% to 22%, having polled more than 50,000 people online since election day.

The corresponding figures it gave in its poll after the 2015 election were 36% to 32% - if correct that is a huge swing among young voters.

Ipsos Mori's methodology is somewhat different - it spoke to 7,500 people before the election and then adjusted its findings based on the actual results.

But it also found a big swing to Labour among younger voters, beating the Conservatives by 62% to 27% among 18- to 24-year-olds, compared with a 43% to 27% split in 2015.

It said: "All the swing to Labour was among under-44s," although it actually found a bigger swing in the 25-34 age group than in the 18-24s.

Lord Ashcroft's much smaller exit poll puts support for Labour among young people even higher, with 67% of 18 to 24 year olds voting Labour and 18% voting Conservative.

YouGov and Ipsos Mori also estimated the turnout among groups of voters.

YouGov found that about 58% of people between the age of 18 and 24 voted, while Ipsos Mori estimated that it was 54%. Both of those figures are a proportion of all 18- to 24-year-olds, not just those who are registered to vote.

If accurate, those figures would be considerably higher than recent elections, but lower than the widely quoted but poorly sourced figure of 72%, which Reality Check wrote about.

We don't have comparable YouGov figures from the 2015 election. The corresponding figures from Ipsos Mori were 38% of all 18- to 24-year-olds and 43% of those registered to vote.

The overall turnout (and these are actual figures - not based on polling) was 69%, compared with 66% in 2015, so it appears that the youth vote increased by considerably more than the overall turnout.

Among the other findings of the YouGov poll was that 49% of graduates voted Labour compared with 32% voting Conservative. In 2015 that figure was 34% Labour and 35% Conservative.

That compares with people with no academic qualifications above GCSE, who in 2017 split 33% for Labour and 55% for the Conservatives and in 2015 split 30% for Labour and 38% for the Conservatives.

Ipsos Mori found broadly the same result broken down by level of education.

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