One of the biggest insurance companies in Britain is to use social media to analyse the personalities of car owners and set the price of their insurance.

The unprecedented move highlights the start of a new era for how companies use online personal data and will start a debate about privacy.

Admiral Insurance will analyse the Facebook accounts of first-time car owners to look for personality traits that are linked to safe driving. For example, individuals who are identified as conscientious and well-organised will score well.

The insurer will examine posts and likes by the Facebook user, although not photos, looking for habits that research shows are linked to these traits. These include writing in short concrete sentences, using lists, and arranging to meet friends at a set time and place, rather than just “tonight”.

In contrast, evidence that the Facebook user might be overconfident – such as the use of exclamation marks and the frequent use of “always” or “never” rather than “maybe” – will count against them.

The initiative is called firstcarquote and was officially meant to launch this week but that was delayed at the last minute on Tuesday night. It is aimed at first-time drivers or owners – although anyone with a licence can apply. The scheme is voluntary, and will only offer discounts rather than price increases, which could be worth up to £350 a year. However, Admiral has not ruled out expanding firstcarquote.

The rapid growth of social media and personal technology has given insurance companies and employers swaths of data they can access to analyse customers or employees. As well as Admiral’s car insurance scheme, insurers are looking at how they can use the rise of smartwatches and fitness trackers to monitor people’s health. For example, Vitality is currently selling the Apple Watch to health and life insurance customers, with the final price dependent on how much exercise customers do while owning the watch.

Admiral says that firstcarquote offers a way for young drivers to identify themselves as safe rather than having to wait years while they build up a track record and a no claims bonus.

Dan Mines, who led the firstcarquote project at Admiral, denied that it was invasive of personal data.

“It is incredibly transparent. If you don’t want to use it in a quote then you don’t have to,” he said. “We are doing our best to build a product that allows young people to identify themselves as safe drivers.”

Mines said Admiral could eventually develop the scheme further, meaning it could include other social media sites and increase the price of insurance for some drivers.

“This is very much a test product for us. This is innovative, it is the first time anyone has done this,” he said. “It is a test, this is early days. The data will only ever provide a discount. We will work through that and learn more.

“I think the future is unknown. We don’t know if people are prepared to share their data. If we find people aren’t sharing their data, then we won’t ever get to consider that [expanding firstcarquote].”

The scheme is based around algorithms that have been developed by Admiral. The technology uses social data to make a personality assessment and then, judging against real claims data, analyse the risk of insuring the driver.

Yossi Borenstein, the principal data scientist on firstcarquote, said its algorithm looked for correlations between social media data and actual claims data. The technology will evolve as firstcarquote attracts customers and gathers more evidence about the correlations, meaning the importance of items identified on social media could change.

Borenstein said: “Just like conscientiousness there are other traits which can be indicative of safe driving. Our algorithm for calculating what ‘safe’ looks like is constantly learning, as we match social data to actual claims data.

“Our analysis is not based on any one specific model, but rather on thousands of different combinations of likes, words and phrases and is constantly changing with new evidence that we obtain from the data. As such our calculations reflect how drivers generally behave on social media, and how predictive that is, as opposed to fixed assumptions about what a safe driver may look like.”

Borenstein insisted that Admiral would not have access to information about what its customers look at on Facebook or what their friends do. The company would only have access to the information gathered during the quote process and would have no ongoing access.

“If this is successful, it could be revolutionary,” he said. “It could be truly transformational.”

An Admiral spokesman said: “The launch of our firstcarquote trial has had to be delayed. We’ve been working closely with Facebook in Europe to get the service ready, and are now addressing a few outstanding issues. We hope that very soon we will be able to offer first-time drivers better deals on their car insurance.”