For domestic flights, it is generally recommended to arrive at the airport at least 1.5 to 2 hours before departure. This allows time for check-in, security screening, and reaching your gate. Some sources suggest 1.5 hours is sufficient if you have no checked baggage and have done online check-in, while others recommend 2 hours, especially for larger airports or peak travel times. For international flights, arriving 2.5 to 3 hours before departure is advised due to additional processes like passport control. Key factors affecting the recommended arrival time include:

• Whether you have checked baggage or only carry-on
• The size and traffic of the airport
• Airline-specific check-in rules
• Whether you have done online check-in
• Time of day and travel period (peak times require more time)

In summary, aim for about 1.5 to 2 hours early for domestic flights and 2.5 to 3 hours for international flights, adjusting for specific circumstances like airport size and baggage requirements.