British people no longer fit into three social classes, with only one in seven in the "traditional working class", a new study has suggested.
The UK also has an "elite" - just 6% of the population - who have savings of more than £140,000, extensive social contacts and education at top universities, according to the BBC's online Great British Class Survey.
More than 160,000 respondents took part in the survey, the largest ever of its kind in the UK, the BBC said.
Researchers found the established model of an upper class, middle class and working class has "fragmented" and there are now seven classes ranging from the "elite" to the "precariat".
Representing 15% of the population, the "precariat" earn just £8,000 after tax, have average savings of £800, with fewer than one in 30 gaining a university education.
Professor Mike Savage, of the London School of Economics and Political Science, carried out the research with Professor Fiona Devine, of the University of Manchester, with the help of BBC Lab UK.
Prof Savage said: "It is striking that we have been able to discern a distinctive elite, whose sheer economic advantage sets it apart from other classes. At the opposite extreme, we have discerned the existence of a sizeable group - 15% of the population - which is marked by the lack of any significant amount of economic, cultural or social capital.
"The recognition of the existence of this group, along with the elite, is a powerful reminder that our conventional approaches to class have hindered our recognition of these two extremes, which occupy a very distinctive place in British society."
Researchers found the "traditional working class" has fallen to just 14% of the total population, and "is fading from contemporary importance". At one in four of the population, the "established middle class" is the largest group, with household income of £47,000 and some "highbrow" tastes. The "emergent service workers" are the sixth group and the youngest, with a mean age of 34 and high proportions of ethnic minorities.
The findings will be presented at a conference of the British Sociological Association on Wednesday, and will be published in this month's Sociology Journal.