When do you need to replace the brakes on your car?

If you don't know how, take it to a local shop. Most retail chains will inspect your brakes for free and let you know. They will visually inspect the brake pads to determine if there is enough life left in the pads to give you a rough estimate on how long you can go before replacing them.

If you notice a vibration or pulsation when braking, you should probably get it looked at as well.