The proportion of firsts handed out by UK universities has soared, with a third of institutions now grading at least one in four degrees with the top honour.
In some cases, the proportion has more than doubled in five years, according to Press Association analysis of official data.
With students now paying up to £9,250 a year in tuition fees, almost all universities and colleges are giving out a higher proportion of firsts than they were in 2010/11.
The findings are likely to spark fresh debate about grade inflation, and whether the centuries-old degree classification system is still fit for purpose.
One expert said some increase is not unreasonable, but that issues such as university rankings may fuel grade inflation.
The PA analysis shows:
:: At 50 UK universities - roughly a third of the total - at least 25% of degrees awarded in 2015/16 were a first, while at 10 institutions, more than a third were given the highest award.
By contrast, in 2010/11 just 12 institutions gave at least one in four degrees a first, and only two gave more than a third the top honour.
:: On average, across all institutions there has been around an eight percentage point rise in firsts in the last five years, the analysis of Higher Education Statistics Agency (HESA) data shows.
:: Just seven institutions have seen a fall in the proportion of firsts.
:: Five universities and colleges have seen the proportion of top honours rise by at least 20 percentage points, while 40 institutions have seen at at least a 10-point hike.
The figures, for the academic years 2010/11 and 2015/16, are based on 148 universities and colleges for which there is comparable data, and exclude degrees rated as "unclassified".
Official figures have previously shown that nationally, almost one in four students (24%) graduated with a first last year.
Nick Hillman, director of the Higher Education Policy Institute (HEPI), said: "Some rise is not unreasonable, given that schools have got better and some universities have increased their entry tariffs so they're getting better quality students."
But he suggested the impact of university league tables could be fuelling grade inflation.
Many institutions now employ staff to compare their results and data with others, he said, and if a university finds itself slipping down the rankings - for example on the proportion of firsts or 2:1s awarded - there is an incentive to improve this.
There are also issues with the external examination system used by many universities, which sees academics from other institutions asked to assess students' work against a university's requirements, he said.
"There are people who think the system isn't as robust as it might be," Mr Hillman said. "It can all be a bit bit cosy - you ask someone you know to be an external examiner."
At the same time, it is often the university itself that has the ultimate power to decide a student's grade.
"A comparison would be if schools could decide how many A grades to give in A-levels - it's a big incentive for grade inflation."
The rise may also be partly down to students working harder, Mr Hillman said, adding that HEPI data does not show an increase in the number of hours students are working.
"As you wander round universities, the student union bars are empty and the libraries and working environments are full.
"They're not putting in more hours, but they are more productive in the hours they are doing."
Mr Hillman suggested that the rise in firsts could be an issue for the new Office for Students to examine.
A spokeswoman for vice-chancellors' group Universities UK said degree classifications are a matter for individual institutions.
"Every one of our universities is unique, with a different subject mix, student body, faculties and departments and, of course, different course curricula and content, which makes comparison difficult, but this diversity is valued by students and staff and this is a strength of the UK sector," she said.
"The sector has changed significantly since 2010, with universities putting more emphasis on the quality of teaching and investing in learning support, alongside the fact that with higher fees, students may be working harder to achieve higher grades."