How do I know if my Vauxhall Astra's brake pads need to be replaced?

I recently bought a used Vauxhall Astra and I'm not sure if the brake pads need to be replaced. What are the signs to look out for and how often should I replace them?

You can check the thickness of your brake pads by looking through the spokes of your wheels. If they are less than 3 millimeters thick, it's time to replace them.

Another way to tell is by listening for a high-pitched squealing sound when you apply the brakes. This is a built-in indicator that your brake pads are worn down.

It's recommended to replace your brake pads every 25,000 to 50,000 miles. However, this can vary depending on your driving habits and the type of brake pads installed.

I suggest getting your brake pads checked by a mechanic every 6 months or whenever you get an oil change. This will ensure your safety while driving.