Sector time
A sector time is the time a driver takes to complete one of three timed sections of a lap. Every F1 circuit is divided into three sectors by the FIA timing system, and each driver's lap is broken down into Sector 1, Sector 2, and Sector 3 splits. Sector times are the unit of analysis for comparing where on a lap a driver gains or loses time.
How the timing works
Each F1 circuit has two sector lines (often called "split points") in addition to the start-finish line. Crossing each line triggers a timestamp from the FIA's timing transponder system. The three resulting splits are the sector times for that lap[1].
Sector boundaries are not always at the same percentages of lap length. Each circuit's sectors are defined by the FIA before the race weekend and remain consistent across all sessions of that weekend.
Purple, green, and yellow sectors
When the broadcast shows sector colour coding:
- Purple: the fastest sector time of the session so far. Anyone who sets a new fastest sector "goes purple".
- Green: faster than the driver's own previous best for that sector, but not faster than the session purple.
- Yellow: slower than the driver's previous best.
A lap that goes "purple-purple-purple" (purple in all three sectors) is the session's optimal hypothetical lap. Note: this is not always the same as the fastest actual lap, because no single driver may have strung together all three best sectors in a single lap.
Why teams analyse sector times
:::analysis A faster lap time tells you the driver was quicker overall. Sector times tell you where. That distinction matters for setup decisions:
- A driver consistently losing time in a slow-corner sector may need more mechanical grip or rear traction.
- A driver losing time in a high-speed sector may need more downforce or a different aero balance.
- A driver gaining in one sector and losing in another may be over- or under-rotating the car through a specific corner type.
By Saturday qualifying, every team has a sector-by-sector model of where their car gains and loses against the field. The setup changes between Q1 and Q3 are often informed by sector deltas more than by lap-time deltas. :::
Sector time vs lap time
A lap time is the sum of three sector times. Sector times are useful for analysis; lap time is the unit of competition.
The strongest commentary observation about a session often uses both: "Hamilton was purple in Sector 1, lost three tenths in Sector 2 traffic, and recovered most of it in Sector 3."
Related
- [1]FIA Formula 1 Sporting Regulations (fia). Accessed 2026-05-25.
- [2]Formula 1 official information (formula1). Accessed 2026-05-25.