You can choose one of three types of distances measured by isochrones:
Walking distance (5 and 10 minutes)
Driving distance (3 and 5 minutes)
Fixed distance (250 and 500 meters)
To change the distance, open the Configure menu by clicking the corresponding tab in the top right corner. Choose the option you want to implement, and then click Select.

A confirmation dialog will pop up to ensure you want to make this change. Click Confirm to proceed.