The taxi fare from Auroville to Chennai Airport can vary depending on several factors such as the type of cab, the service provider, and the time of booking. However, as a general estimate:

Sedan (e.g., Swift Dzire, Toyota Etios): ₹2,500 to ₹3,500 for a one-way trip.
SUV (e.g., Toyota Innova, Mahindra Xylo): ₹3,500 to ₹5,000 for a one-way trip.
Some services may also charge additional fees for tolls, night travel, or extra luggage. If you’re booking local taxi operators, you might also find offers or discounts depending on the time of booking.

It’s a good idea to book the cab in advance to secure the best rates and ensure availability.