How much does an oven cost to run compared with an air fryer?

The air fryer versus oven comparison is usually quoted as a single percentage, which is meaningless without knowing what is being cooked. The energy an appliance uses is its power multiplied by the time it is actually drawing that power, and both of those differ enormously between a tray of chips and a Sunday roast. What follows is the calculation with the honest complications left in.

Step by step

1. Find both appliances' real wattage.On the rating plate: the oven's is usually on the door frame or cavity edge, the air fryer's underneath. A typical single fan oven is 2,000 to 2,500W; a typical air fryer is 1,400 to 2,100W. Note that these are much closer than people assume — the air fryer does not win on power.
2. Take your unit rate off your electricity bill.Pence per kWh, not the standing charge. Use your own number. Every worked example below uses 25p per kWh purely as an illustration; substitute yours and the answers change proportionally.
3. Apply the duty-cycle correction that most comparisons skip.Neither appliance draws its rated power continuously. Both draw full power to heat up, then cycle the element on and off to hold temperature. A rough working assumption is full power during preheat, then around 40 to 50 per cent of rated power thereafter. Ignoring this overstates both figures by a lot.
4. Do the small-load comparison.One portion of chips. Oven: 15 minutes preheat at 2,200W plus 25 minutes at roughly half that, which is about 0.55 plus 0.46, so around 1.0 kWh, or 25p at the example rate. Air fryer: 3 minutes preheat at 1,700W plus 18 minutes at roughly half, which is about 0.09 plus 0.26, so around 0.35 kWh, or roughly 9p. The air fryer costs about a third as much.
5. Do the full-load comparison.A roast plus two trays of vegetables. The oven does it in one 90-minute run: about 0.55 preheat plus 1.65, so around 2.2 kWh, or 55p. The air fryer would need three or four batches, each with its own preheat, and cannot take the joint at all. Per meal, the oven wins outright.
6. Recompute for how you actually eat.Multiply your own per-use figures by how often each happens in a week. A household that cooks four small weekday meals and one roast saves meaningfully by moving the four to an air fryer and leaving the roast in the oven. A household that batch-cooks does not.
7. Sanity-check with the annual figure on the energy label.An oven's label gives kWh per cycle for a standard test load. It is a comparison tool between ovens, not a prediction of your bill, but it is a useful reality check that your own arithmetic is in the right order of magnitude.

Tips

• The single biggest saving on either appliance is not preheating when the recipe does not need it, and not preheating for longer than the appliance takes. Most ovens are at temperature well before people put food in.
• A plug-in energy monitor on the air fryer for a week gives you a measured figure rather than an estimated one, and it costs very little. An oven on a fixed circuit cannot be measured this way.
• Batch cooking in the oven and reheating in the microwave beats both appliances on cost per meal by a wide margin, because reheating is the cheapest cooking there is.
• Cooking two things in the oven at once halves its cost per dish immediately, which is often a bigger win than switching appliance.

Common mistakes

• Comparing rated wattages directly — An oven and an air fryer have surprisingly similar power ratings. The difference is volume heated and time held, not watts, so a wattage comparison points the wrong way.
• Ignoring preheat on the oven and counting it on the air fryer — Preheat is the largest single block of energy in a short oven cook and a trivial one in an air fryer. Counting it consistently is what makes the comparison honest in the air fryer's favour.
• Assuming the saving scales to every meal — It is a small-load saving. Once the food does not fit in one basket, the batches multiply the preheats and the advantage disappears.

Questions people ask