F1 testing explained: Key questions answered over vital pre-season running

F1 testing may look on the outside as close as the sport comes to cars going simply around a circuit repeatedly, but there is so much more to it than that.

In Bahrain, all 10 teams will see their brand-new cars take to the track with their 20 drivers as they get set for the new season, looking to get as many laps under their belts as possible in the process.

F1 testing explained: All you need to know about pre-season running

What is F1 pre-season testing and why is it so important?

F1 testing is a crucial part of the calendar because, while it is not officially a Grand Prix event, teams use it as the proving ground for their new cars before the season starts.

Having undergone a build process in separate departments, it is the first time that the team’s new components are used together as the cars look to undertake the vital job of correlating the data from their wind tunnel and computer simulations into the real world and, the closer that data matches, the better chance the team has of being able to extract performance from their car.

McLaren confirmed that, on a race weekend, a Formula 1 car runs with around 300 data sensors on it, but during F1 testing, that number is “much, much higher” as the team looks to learn as much as possible about its new car.

On top of that, it is the chance for teams to make sure their procedures are up to scratch for the new season, making sure everything works properly and, perhaps most importantly from the drivers’ perspective, giving those behind the wheel the chance to get a feel of their new car and work in close proximity with their team before the season starts.

F1 testing is always important any year, even when regulations are stable such as in 2025, but when a change of regulations come in 2026, this time becomes even more precious as teams look to learn about all-new cars.

When and where is F1 testing?

F1 testing in 2025 takes place at the Bahrain International Circuit from Wednesday 26 until Friday 28 February, with a morning session from 10am until 2pm [7am-11am GMT] followed by an hour’s lunch break, before running resumes from 3pm until 7pm [12pm-4pm GMT] on all three days.

Will F1 testing be broadcast on television?

Yes, Sky Sports F1 will be carrying live coverage of F1 testing across all three days in the UK, ESPN+ will be showing testing live in the United States, while it will also be available to stream online on F1 TV Pro.

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Will we be hearing the word ‘sandbagging’ in F1 testing and what does it mean?

Predictable like the tide, the word ‘sandbagging’ comes up every year in F1 testing – and it’s a term that is used for a very good reason.

With teams looking to hide their true pace until qualifying in Melbourne, they are likely to stop their drivers from putting in a lap time that is too eye-catching for their rivals.

To do this, teams can run their car in more conservative engine modes, drive with higher fuel loads, get their driver to back off at certain points in the lap, add more ballast to the car – anything to give the effect of adding sandbags to the car to make it ever-so-slightly slower.

Will the fastest team in F1 testing be the quickest at the first race?

It’s not impossible, but don’t read too much into testing times. As a result of ‘sandbagging’ above, it’s rare that the leaderboard from testing will be indicative of the competitive running order – but there are clues that can be garnered as to a team’s confidence.

Reliability is always the biggest first step, seeing if drivers are able to run long stints uninterrupted, alongside drivers potentially putting in a race simulation and watching average lap times to see what their speed looks like.

How the drivers speak after testing is usually something of a clue to their overall pace, too, with those talking with a quiet confidence often happy with where they may end up, and those to vocalise any early issues with the new car potentially highlighting work to be done.

Who is taking part in F1 testing and when?

All 20 drivers will get time behind the wheel in Bahrain, with teams giving their drivers a day and a half each to get to grips with their new machines.

For some, it will be their main chance to work with their new colleagues as they move teams, and for the swathe of rookies joining the grid in 2025, it is a vital opportunity to gain time behind the wheel of a Formula 1 car before they do so in anger in Melbourne.

We have broken down each team’s plans for the 2025 Bahrain test here.

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