[1] Similarly to the previous year,[2] Mercedes covered the most mileage overall, despite some power unit reliability issues (which was shared by customer team Williams).

[7] Sebastian Vettel was scheduled to be the first to drive for Scuderia Ferrari, but missed day one of testing with flu-like symptoms, and his place was taken by Charles Leclerc.

[8] The Circuit de Barcelona-Catalunya has been used as the venue for pre-season testing for many years,[9] and is favoured by teams because its mix of low and high speed corners.

[1] Testing provides the teams with the opportunity to experiment with different versions of the same part, with many employing aero rakes[10] and flow-viz[11] paint to understand the aerodynamic performance of the car.

[15] Kimi Räikkönen set the fastest time of 1:17.091 then caused the first and only red flag of the day when his Alfa Romeo stopped on track coming up to turn 9.

There were three red flags, one when Vettel spun, another for Latifi's breakdown, and a third towards the end of the session when both Verstappen and Daniil Kvyat stopped on track.

The final day of testing was relatively incident free, with no red flags,[19] and many of the drivers focusing on longer runs, such as Hamilton, Leclerc, Carlos Sainz, and Romain Grosjean.

Pirelli estimated in the previous year that the performance gap between each tyre compound was around 0.6-0.7 s, although this varied based on numerous factors.