Brits who shop online are missing out on £4.6bn worth of savings each year by not shopping around to compare prices, according to retail price comparison site Pricesearcher.

The site’s research found 48 million Brits shopping online could each save £95 a year by comparing prices. The top three retail categories boasting the biggest savings are auto parts, jewellery, and DIY – with average savings of £186, £33, and £32 respectively.

Pricesearcher has launched a free online browser extension to check and compare the prices on more than 10,000 shopping websites.

Browser extensions or add-ons are small programs you can download to add new features to your browser. The extensions available will vary depending on which browser you use, with Firefox and Chrome typically having the most options.

For any of the 150 million products in its index, Pricesearcher’s browser extension checks which other retailers are selling the same product, and at which price. Pricesearcher compares prices from Amazon and eBay, as well as high-street retailers, brand sites, online sellers such as ASOS, and deal sites such as Groupon.

The extension alerts shoppers to all their buying options, with a simple message appearing on screen.

Sam Dean, CEO and founder of Pricesearcher, said: “Our mission is simple; to give online shoppers peace of mind they will pay the right price for a product. Despite the vast online shopping world, it is more common for shoppers to go straight to the website they want to buy from, rather than shop around, compare prices, and bag the best deal.

“Even worse, most Brits don’t know that Google Shopping – for example – only displays paid listings.  No retailer pays to appear on Pricesearcher; our free platform encourages them to showcase all their products, giving shoppers total price transparency and the complete view of all their buying options, in one place.”

The launch of Pricesearcher’s online browser extension comes as Amazon Prime Day gets underway. The 48-hour sale takes place on 15 and 16 July and sees the online retail giant slash the price of thousands of products for Prime members.