How much following distance a driver should keep to safe in an urban area?

The recommended following distance in an urban area is usually around 2-3 seconds. To measure this distance, you can use a simple trick: pick a fixed object on the side of the road ahead of the vehicle in front of you, such as a sign or a tree. When the rear of the vehicle in front of you passes that fixed object, start counting "one thousand and one, one thousand and two, one thousand and three". If you reach the fixed object before you finish counting, you are following too closely and should increase the following distance.