Formula One 2026 rules explained: new engines, boost buttons and Z‑Mode aero. Photo / Getty Images
Formula One will undergo one of the biggest overhauls in its 75-year history in 2026. Arguably, its biggest ever. Never before has there been such a fundamental redesign of both power units and chassis in the same season.
In an effort to improve the racing, cars this season will be smaller and lighter. Fifty per cent of the power will come from a battery, with drivers able to deploy extra boosts of power as they lap.
Will it make the action any better to watch? The proof of the pudding will be in the eating, but Lando Norris, McLaren’s newly crowned champion, has already predicted “chaos” for the season ahead.
To help get you up to speed, Telegraph Sport explains what has changed.
While the 1.6-litre V6 engine remains, how it generates power is shifting dramatically. From 2026, the power will be split almost equally between the petrol engine (ICE) and electric power.
There will be five power unit manufacturers supplying the 11 teams, with Honda returning as a full works partner (for Aston Martin), and newcomers Audi and Red Bull-Ford joining established manufacturers Mercedes and Ferrari.
Electrical boost from the Motor Generator Unit Kinetic (MGU-K) – which turns kinetic energy generated by the brakes into electricity for the power unit – will jump from 120 kilowatts (kW) to 350kW, a near 200% increase.
Meanwhile, the complex MGU-H (which recovered heat from the turbo) is being removed to lower costs. This helped attract new manufacturers like Audi and Ford.
This has already triggered the first controversy of the season, with Mercedes accused by their rivals of exploiting a loophole in the compression ratio regulations that means their engine can produce more power when hot than it can when tested at “ambient” temperatures, as per the rule book.
Here, we explain what the compression ratio is and how Mercedes are believed to be operating their engine.
The FIA, Formula One’s governing body, announced on Wednesday (local time) that the five engine manufacturers would be given the chance to vote on a change to the way in which compression ratios are measured. But it added that the proposal, if voted through, would only come into effect on August 1, giving Mercedes the green light to use their “loophole-exploiting” power unit for at least the first half of the season.
This is now the main battleground and one that Norris has said could lead to “chaos”.
For the drivers, it comes down to how and when to use the electrical power at their disposal. It promises to put more responsibility in their hands. This season will feature a “boost button”, which drivers can press at any point on the lap to deploy maximum electrical energy for attacking or defending, provided they have enough charge.
As well as that, there will be an “overtake button” (replacing the Drag Reduction System, or DRS, when the rear-wing flap opened up to reduce downforce when driving in a straight line), which will give drivers an additional 0.5MJ (megajoules) of electrical energy on the following straight, provided they are within one second of the car in front at a detection point.
The flipside to using all these boosts is that drivers will have to get very good at recharging their batteries. We could see drivers “lift and coast” – referred to by drivers as “LiCo” – early into braking zones, even on qualifying laps, to recharge the battery for longer, higher-power acceleration periods. Failure to do so could lead to “clipping”, running out of battery power, which would result in immediate loss of half the car’s power.
Norris said this month that the new way of driving would take some getting used to and could lead to “yo-yoing” as cars repeatedly pass one another.
Max Verstappen, meanwhile, was heavily critical after the first Bahrain test. “I just want normal driving. How it should be. Without having to go, ‘Oh, if I brake a bit longer ... or less or more ... or one gear up or down ... ’ you know, that it so heavily impacts the performance on the straights, and stuff like that.”
Modern-day Formula One cars are often criticised for being too large and cumbersome. The 2026 rules aim for a “nimble” car concept to improve racing. Minimum weight, including the driver, will drop by 30kg (from 798kg to 768kg) while the chassis will be 20cm shorter in length and 10cm narrower. To save weight and reduce drag, the 18-inch tyres are also becoming narrower (2.5cm narrower at the front and 3.0cm at the rear).
The cars will run on “100% sustainable” fuel, made from non-food waste or carbon capture, meaning no new fossil carbon is burned. It is still unclear whether this will be a big area of competition, though the rumours are some fuels will be a lot more efficient than others. Reports this week claim some engine suppliers, such as Mercedes, are struggling to get their sustainable fuels to meet the new regulations.
One thing is clear: it is very expensive. Aramco’s fuel for Aston Martin in 2026 is set to cost $170-$225 per litre, which is five to 10 times more than 2025’s E10 blend.
The old DRS is being replaced by a more advanced system that adjusts the whole car’s aerodynamics.
Cars will automatically go into what will be called Z-Mode when cornering. This is the default high-downforce setting where wings stay shut to provide maximum grip for turning. In this mode, both the front wing and rear wing will look very similar to last season.
They will then switch to X-Mode on straights, a low-drag setting where both the front and rear wings open up to reduce drag and increase top speed. Video footage from pre-season testing has effectively shown wings to disappear when X-Mode is activated, thanks to clever hydraulic systems.
Unlike the old DRS, all drivers can use this on every lap, regardless of how close they are to another car.