Session API

Reference for FastF1 Session class - load and access session data

The Session class is the primary interface for accessing Formula 1 session data including lap times, telemetry, weather, and results.

Session

Object for accessing session specific data.

Constructor:

event · Event · required

Reference to the associated Event object

session_name · str · required

Name of this session (e.g., ‘Qualifying’, ‘Race’, ‘FP1’)

f1_api_support · bool · default: "False"

Whether the official F1 API supports this event

Sessions are usually created using fastf1.get_session() rather than instantiating directly.

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Properties

event

type · Event

Reference to the associated Event object

name

type · str

Name of this session (e.g., ‘Qualifying’, ‘Race’, ‘FP1’)

date

type · pd.Timestamp

Date at which this session took place

drivers

type · list

List of all driver numbers (as strings) that participated in this session. Available after calling load().

results

type · SessionResults

Session results with driver information. Available after calling load().

laps

type · Laps

All laps from all drivers in this session. Available after calling load() with laps=True.

car_data

type · dict

Dictionary of car telemetry (Speed, RPM, etc.) keyed by driver number (string). Each value is a Telemetry object. Available after calling load() with telemetry=True.

pos_data

type · dict

Dictionary of car position data (X, Y, Z coordinates) keyed by driver number (string). Each value is a Telemetry object. Available after calling load() with telemetry=True.

weather_data

type · pd.DataFrame

DataFrame containing weather data for this session. Available after calling load() with weather=True.

session_status

type · pd.DataFrame

Session status data (Started, Finished, Aborted). Available after calling load() with laps=True.

track_status

type · pd.DataFrame

Track status data (yellow flags, red flags, etc.). Available after calling load() with laps=True.

race_control_messages

type · pd.DataFrame

Race control messages for this session. Available after calling load() with messages=True.

session_info

type · dict

Session information including meeting, session, country and circuit names and unique identifier keys.

total_laps

type · int | None

Originally scheduled number of laps for race-like sessions. Available after calling load() with laps=True.

t0_date

type · pd.Timestamp

Date timestamp marking the beginning of the data stream (when session time is zero). Available after calling load() with telemetry=True.

session_start_time

type · pd.Timedelta

Session time at which the session was started. Available after calling load() with laps=True.

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Methods

load()

Load session data from the supported APIs.

laps · bool · default: "True"

Load laps and session status data

telemetry · bool · default: "True"

Load telemetry data (car_data and pos_data)

weather · bool · default: "True"

Load weather data

messages · bool · default: "True"

Load race control messages

livedata · LiveTimingData | None · default: "None"

Optional locally saved livetiming data to use as data source instead of API

Without specifying any options, all data is loaded by default. Loading all data is recommended as FastF1 uses data from multiple sources to provide the most accurate results.

Example:

import fastf1

# Load all data (default)
session = fastf1.get_session(2023, 'Monaco', 'Race')
session.load()

# Load only specific data
session = fastf1.get_session(2023, 'Monaco', 'Q')
session.load(laps=True, telemetry=False, weather=False, messages=False)

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get_driver()

Get a DriverResult object containing information about a specific driver.

identifier · str · required

Driver’s three letter identifier (e.g., ‘VER’) or driver number as string

return · DriverResult

DriverResult object with driver information

Example:

session = fastf1.get_session(2023, 'Monaco', 'Race')
session.load()

# Get driver by abbreviation
ver = session.get_driver('VER')
print(ver['FullName'])  # 'Max Verstappen'

# Get driver by number
ham = session.get_driver('44')
print(ham['TeamName'])  # 'Mercedes'

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get_circuit_info()

Returns additional information about the circuit hosting this event.

return · CircuitInfo | None

CircuitInfo object with corner locations, marshal lights, marshal sectors, and track map rotation. Returns None if information is unavailable.

The circuit information is manually created and not highly accurate, but it’s useful for annotating data visualizations.

Example:

session = fastf1.get_session(2023, 'Monaco', 'Race')
session.load()

circuit_info = session.get_circuit_info()
print(circuit_info.corners)

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Complete Usage Example

import fastf1
import matplotlib.pyplot as plt

# Get and load a session
session = fastf1.get_session(2023, 'Monaco', 'Race')
session.load()

# Access session properties
print(f"Session: {session.event.EventName} - {session.name}")
print(f"Date: {session.date}")
print(f"Drivers: {session.drivers}")

# Access results
results = session.results
print(results[['Position', 'Abbreviation', 'TeamName']])

# Access laps
laps = session.laps
fastest_lap = laps.pick_fastest()
print(f"Fastest lap: {fastest_lap['LapTime']}")

# Access telemetry
ver_laps = laps.pick_drivers('VER')
ver_fastest = ver_laps.pick_fastest()
ver_tel = ver_fastest.get_telemetry()

# Plot speed
plt.plot(ver_tel['Distance'], ver_tel['Speed'])
plt.xlabel('Distance (m)')
plt.ylabel('Speed (km/h)')
plt.title('Verstappen Fastest Lap - Speed Trace')
plt.show()

# Access weather data
weather = session.weather_data
print(weather[['Time', 'AirTemp', 'TrackTemp', 'Rainfall']])

# Access race control messages
messages = session.race_control_messages
print(messages[['Time', 'Category', 'Message']])