55 terms, A to Z
- 2026 Season Pack format
- The newer of the two UDP telemetry layouts F1 25 can send. It carries 24 cars per packet instead of 22, and several per-car entries changed size. StintLab reads it with a packet-by-packet size check.What changed in 2026 →
- Apex
- The point on the inside of a corner that the car passes closest to. The corner's slowest point usually sits near it.Anatomy of a corner →
- Assists
- Driving aids: steering, braking, gearbox, ERS and DRS assists and the racing line, plus ABS and traction control. StintLab records the first six with every F1 lap and only matches laps whose assists agree; ABS and traction control are not recorded.Assists and fair comparisons →
- Baseline
- A run of laps in fixed conditions — one car, one track, one set of settings — that later sessions are measured against.Driving a baseline →
- Brake point
- Where braking for a corner starts. StintLab takes it as the first sample where the brake reaches 10%.Braking points →
- Brake-point spread
- How far a corner's brake point moves from lap to lap, measured as a standard deviation in metres across a session's counted laps. StintLab shows it for every corner, and the session's debrief names the least repeatable one when it is 10 m or more.Which corner wanders →
- Braking zone
- The stretch from the brake point until the brake drops below 5%. In StintLab a press that never reaches 15% is a dab, not a braking zone.How a braking zone is found →
- Coasting
- Neither pedal pressed. Sometimes deliberate, as in lift and coast; often hesitation that costs time.
- Compound
- The type of tyre. F1 25 reports both a visual name — Soft, Medium, Hard, Intermediate, Wet — and the actual compound behind it, such as C3.Tyres →
- Consistency
- How closely a driver repeats their laps. StintLab measures it as the spread of the counted laps, alongside the typical lap.Consistency →
- Counted lap
- A lap that is valid, timed, driven from the start line and not through the pits. Only counted laps set a best lap, a best sector, the consistency figure or the optimal lap.The rules →
- Delta
- The running time gap between two laps at the same point of the track. Where the delta line climbs, the lap is losing time right there.Reading the delta line →
- Distance-based sampling
- Recording a lap as a sample every few metres of track rather than every few milliseconds, so two laps land on the same axis and the gap between them is a subtraction. StintLab keeps a sample once the car has moved 5 m or more, so how close they sit also depends on how often the game sends data.Distance, not time →
- DRS
- Drag Reduction System: a flap in the rear wing that opens on designated straights to cut drag and add straight-line speed. Real F1 replaced it with active aerodynamics from 2026; the F1 25 game still has it, and StintLab records whether it was open at every trace sample.
- Entry speed
- The car's speed where braking for a corner starts.
- ERS
- Energy Recovery System: the hybrid system that harvests energy and deploys it as extra power. StintLab records the ERS assist setting but not deployment or battery level.
- Exit speed
- The speed a car carries out of a corner. It sets the speed down the following straight until both cars reach top speed, which is why time lost on a straight is often decided in the corner before it.Reading down the traces →
- Flashback
- The F1 games' rewind. StintLab restarts the lap's trace when distance goes backwards, and drops the fuel and pit readings from before the rewind rather than counting them twice — so that lap's fuel figure covers only part of it.How laps are judged →
- Flying lap
- A lap started at speed from the start line, as opposed to an out-lap from the pits.
- Gap at the line
- The official difference between two lap times, as the game timed them.
- In-lap
- The lap that ends in the pit lane. StintLab marks it as a pit lap: kept for strategy, never used for pace.
- Invalid lap
- A lap the game has invalidated, usually for exceeding track limits. StintLab keeps it listed but it sets nothing — and once a lap is invalid it stays invalid to the line, even if the game clears its flag.Invalid laps →
- Lift and coast
- Lifting off the throttle before a braking zone and rolling for a moment before braking, to save fuel or energy at a small cost in lap time.
- MFD
- Multi-Function Display: the in-car display in the F1 games that shows fuel, tyres and other settings. StintLab keeps the game's MFD fuel estimate, in laps, with each lap.Fuel →
- Minimum speed
- The slowest point of a corner, usually just after the brake is released. Usually the most telling number for a corner.The braking table →
- Mini-sector
- A smaller timed split inside a sector, used by live timing to show gains and losses in finer detail.Mini-sectors →
- Optimal lap
- The quickest a driver got through each 100 m of the lap in one session, added up. Every piece of it happened, but not in one lap.The optimal lap →
- Out-lap
- A lap started from the pit exit rather than the start line. In F1 telemetry its lap distance is negative until the line. StintLab lists it but never counts it.
- Overcut
- Staying out longer than a rival before pitting, hoping to gain time on track while they are on their out-lap.
- Packet
- One message of UDP telemetry. F1 25 sends many types — session, lap data, car telemetry, motion, car status and more. Most carry an entry for every car; a few, such as the session and event packets, describe the session or a single moment.The packets StintLab reads →
- Personal best
- A driver's quickest counted lap at a circuit. In StintLab's season record it stands from the first counted lap there.
- Pit loss
- The time a pit stop costs against staying on track — more than the stationary time, less than the whole time in the lane.Pit stops →
- Practice plan
- StintLab's comparison of your lap with a target: the gap every 100 m and up to three sections ranked by what they cost, each with evidence and a drill.The practice plan →
- Purple sector
- The fastest time anyone has set in that sector during the session. Green is a driver's own best that is not the fastest overall; yellow is slower than their own best.Sector colours →
- Racing line
- The path through a corner that allows the most speed. Also the in-game assist that draws a suggested line on track, which StintLab records as a setting.
- Reference lap
- The lap another is compared against. In StintLab, a lap file imported from someone else is a reference: it can be a target but never counts as your driving.Importing a reference →
- Sector
- One of the three timed parts of a lap, divided by timing lines. Sectors are not equal in length.Sectors →
- Send rate
- How many times a second the game sends telemetry. It does not change lap times; it changes how finely a lap can be traced at high speed.Which send rate →
- Session
- One run in the game — practice, qualifying, a sprint, a race or a time trial. StintLab gives a restarted session its own identity, so its lap numbers never collide with the first run's.
- Slipstream
- The reduced-drag air behind another car. Following closely — a tow — adds straight-line speed with no change in the driver's inputs.
- Speed trace
- A car's speed plotted over the lap. Plateaus are straights, valleys are corners.The speed trace →
- Speed trap
- A point on the circuit where top speed is measured. StintLab shows the fastest speed-trap reading the game reported as the session's top speed.
- Spread
- The slowest counted lap of a session minus the quickest — StintLab's consistency figure.Spread and the typical lap →
- Stint
- A run of laps on one set of tyres, between pit stops or restarts.
- Target lap
- The lap you chase. StintLab picks the fastest valid, fully traced lap in your history that matches the session's game, track, car, weather, session type and settings.How the target is chosen →
- Theoretical best
- A driver's best time in each sector, from any laps of one session, added together.Theoretical best →
- Time available
- The best lap minus the optimal lap (or minus the theoretical best when there is no optimal lap): time already driven, just never in one lap.Time available →
- Track limits
- The boundaries of the circuit, usually the white lines. In F1 25, cutting a corner invalidates the lap; repeated offences bring warnings and penalties.
- Trail braking
- Releasing the brake progressively into a corner instead of all at once before turn-in, so the car is still slowing as it starts to turn. It shows as a tapering brake trace.Reading the pedals →
- Traction
- The grip available to put power down, above all on corner exit. The throttle trace coming out of a slow corner is a traction story.
- Typical lap
- The median counted lap of a session — a better picture of your pace than your best lap, and one bad lap barely moves it.
- Tyre degradation
- The loss of a tyre's performance as it wears and heats up. It is why lap times drift over a stint and why strategy exists.
- UDP telemetry
- The way F1 25 broadcasts its data: small network packets sent many times a second to an address and port you choose — for StintLab, 127.0.0.1 and 20777 on the same PC.F1 25 telemetry settings →
- Undercut
- Pitting earlier than a rival to use fresh tyres' extra speed and come out ahead when they stop.
- Wear
- How much of a tyre has gone, as a percentage per wheel. StintLab keeps the last fresh reading of each lap.
Questions
What is F1 telemetry?
The data an F1 car — or the F1 game — produces about itself while it is driven: speed, throttle, brake, steering, gear, position, lap and sector times, fuel, tyres and more. Teams use it to understand the car and the driver; F1 25 broadcasts its own version as UDP telemetry.
What is the most useful telemetry channel for a beginner?
Speed, read against distance, followed by the delta between two laps. The speed trace shows where the corners are and how slow each one is; the delta shows where the time goes. Throttle and brake explain why.