Martin Lewis has revealed why using an air fryer might be more expensive than an oven.
Millions of Brits use the countertop convection oven as a quick and easy way to heat up food.
But the UK’s most-loved money saving expert has revealed why a traditional oven or microwave might be a better option.
Speaking on his Martin Lewis Podcast, he explained you shouldn’t use an air fryer ‘as a rule of thumb’.
‘A microwave gives you consistent heat whereas an oven is warming up to full temperature and then topping it up so it isn’t running at full power the whole time,’ he said.
‘If you were doing a full roast dinner and you were cooking many [jacket potatoes], it’s probably cheaper [putting them in the oven] than putting five or six jacket potatoes in a microwave because each additional object you put in a microwave, you need to keep it on longer because a microwave just heats the individual object.’
However he added that for small amounts of food it’s often more efficient to use an air fryer.
‘General equation is, find the wattage of an item, then work out how many kilowatts or what fraction of a kilowatt it’s using, then multiply that by 34p per hour of use.
He explained that ovens tend to have be about 2000W while a microwave is about half that.

Martin Lewis has revealed why using an air fryer might be more expensive than an oven.
‘An oven is going to be about 2,000W. If you had a 1,000W microwave and you put it on for 10 minutes, one KWH for a sixth of an hour, a sixth of 34p is about 6p.
‘So it’s 6p turning the microwave on for that amount of time.
‘An oven costs 21p to use on average and a 800W air fryer costs 13.6p to use.
‘But if you own an air fryer that is a lot more powerful, you could be using near enough the same energy as an oven.
‘For example the 2,000W air fryer costs 34p per use, that’s 13p more than an oven.
‘And the biggest factor is the quantity of food you’re cooking.
‘Cooking the same thing twice in an 800W air fryer could cost you more than 26p, which is more expensive than cooking in the oven.’
‘If you’re cooking something small and simple in there, it’s probably cheaper in the microwave and similarly the air fryer,’ he continued in the podcast, first made in 2022.
In 2022, reviewers at Which? compared a Morphy Richards fryer with microwaves, hobs and ovens to test if it can cook a whole chicken.

Speaking on his Martin Lewis Podcast, he explained you shouldn’t use an air fryer ‘as a rule of thumb,’.
They also steamed vegetables, cooked chips and baked a cake in different kitchen appliances and compared them on cooking time, energy use and cost.
The researchers found that air fryers proved up to three times cheaper than a conventional oven to run, and cooked the food equally as well or even better.
It comes after Brits were left in shock after discovering a hidden feature in their Ninja air fryer which could transform the way they cook.
The helpful tool was pointed out in a TikTok by social media user @bowesy5, who revealed they had just discovered something about their favourite kitchen gadget.
In the video, which has been shared almost 60,000 times, the TikToker opened up a discreet side compartment on her large air fryer and pulled out a neatly packed meat prong.
The handy tool is used to ensure meat is cooked properly, in which the tip of the probe contains a temperature sensor which measure how hot the meat is.
The sensor can then send the data to the air fryer or a digital display and tells you exactly how far along the meat is, taking the guess-work out of cooking.
The social media user captioned the clip ‘Did you know?!’ and it seems she wasn’t the only person who was left surprised by the revelation.
Other air fryer users flocked to the comments to share their disbelief with one person writing: ‘HOLD THE FRONT DOOR… goes and checks’ and another commenting, ‘WHAT?!!!! No I didn’t know!! Off to check mine now!!’
A third said: ‘No way I’m checking as soon as I get in’, while another confessed they were running to the kitchen immediately to check this out.
Several TikTok users revealed they knew their air fryer came with a meat probe, but had no idea where it was hidden and wrote underneath the video: ‘I was looking for this!’ while one person commented, ‘I thought we’d lost it in the bin’.
And even Ninja weighed in on the discussion, joking: ‘You lot really don’t read our manuals, do you.’
‘But I’m British,’ one TikTok user replied, and another wrote: ‘Listen I don’t read them unless I mess something up.’
And while many were overjoyed to find out they had a hidden goodie, some were disappointed that their model didn’t include the meat probe.
Only Ninja Foodi MAX Dual Zone Digital Air Fryer come with a digital probe which has been a hit with users woh have taken to the reviews section on Amazon to say: ‘So far, I have roasted a chicken using the probe and I couldn’t believe how quick it cooked.’
Another wrote: ‘What a game changer in the kitchen, easy to use with a very simple set of dials. The probe is a must-get as it totally changes the cooking method with confidence that the food is cooked to perfection.’