You’re doing a spot of online Christmas shopping and see an air fryer that is competitively priced. You don’t recognise the brand, but the reviews are fantastic – five-star raves that say things such as “this product changed my life” and “this is the greatest air fryer ever”.

You buy it, but when it arrives it is clearly cheap and poor quality, and possibly dangerous, too.

Those glowing online reviews were fake.

Although explicitly banned in the UK in April this year, they are continuing to trap consumers.

National Trading Standards (NTS), the consumer protection and enforcement body, issued a warning recently that criminals are using paid individuals, bots and, increasingly, AI to generate fake reviews “on a mass scale”. It says crooks are even creating entire fake review websites, usually linked to specific high-demand products such as air fryers and vacuum cleaners.

Too many glowing reviews should ring alarm bells, say experts. Photograph: Andriy Popov/Alamy

In many cases those who fall for these fraudulent reviews will receive nothing, or they will get a bad-quality item, or a counterfeit of the brand they were expecting.

Estimates vary as to what proportion of all online reviews are fake. A 2023 UK government study estimated that 11% to 15% of all reviews across three common product categories (consumer electronics, home and kitchen, and sports and outdoors) on e-commerce platforms widely used by UK consumers, were not real. Other studies have put the figure at 30%.

What the scam looks like

Traditionally, the business was largely centred on sweatshops located in places such as India and Russia, with people paid to churn out vast numbers of posts to boost a business’s rating. Many of these human-written reviews contain typos, errors and grammar that can be an obvious red flag for UK consumers.

However, technology has transformed this “business”, and the AI-generated reviews are becoming increasingly difficult to distinguish from those written by genuine punters.

It is still often the case that they also do not feature much concrete detail about the product or service, or include phrases seemingly copied from the product description (for example “up to 75% less fat than traditional frying methods”).

They also often go big on vague phrases such as “I can’t believe this is so great”, have hyperbolic headlines such as “these are the greatest hair stylers ever,” and typically don’t include anecdotes.

“Genuine reviews will often be personal and specific to the individual’s experience of using the item, while a fake is more likely to be vague, using generic words and phrases such as ‘amazing’, ‘awesome’, and ‘buy this product’,” says NTS.

Similarly, consumer body Which? says “real reviewers will often want to go into detail”.

It adds that if there is an extremely high percentage of five-star reviews, “consider how likely it is that so many people found the product to be ‘perfect’. Is the reviewer going over the top in the language? For some this may be natural, but if it happens a lot, be wary”.

Alarm bells should also ring if multiple, similar, reviews have been posted all at the same time, or if a reviewer’s account has been activated recently, or has only reviewed a narrow range of products.

What to do

Which? says one way to get a more balanced view of a product is to ignore the five-star reviews. “Check the four, three and two stars and it’s likely you’ll be getting more honest opinions,” it says.

Be particularly careful if you are considering buying a brand you don’t recognise.

And look for “verified” reviews and purchases, where the retailer, or marketplace, has confirmed the item was bought through its site.

Finally, make sure you use trusted review sites.