How to check your brake pads
Quick answer
On many cars you can see the outer brake pad through the wheel spokes with a torch: look at the thickness of the friction material pressed against the disc, not the metal backing plate. Around 3 mm (about 1/8 inch) or less means it is time for new pads soon. If you cannot see the pads, or hear grinding, have a garage check them.
Brake pads are the blocks of friction material that clamp onto the brake disc (rotor) to slow the car. They wear down a little with every stop. Checking how much is left takes ten minutes, needs only a torch, and tells you whether you have months left or need to book a garage now.
Signs your pads need checking now
- A high-pitched squeal on every stop: many pads have a metal wear indicator that squeals on purpose. See why brakes squeal.
- Grinding or scraping: the pad may be worn to metal. Stop driving and read our grinding brakes guide.
- A brake pad warning light, or the red brake warning light.
- The car takes longer to stop, or you feel vibration through the steering wheel or pedal when braking.
How thick is too thin?
| Friction material left | What it means |
|---|---|
| More than about 3 mm (1/8 in) | Fine for now. Check again in a few months. |
| About 3 mm (1/8 in) or less | Book new pads soon. |
| Around 2 mm | Many pad wear sensors and warning lights trigger here. Replace as soon as you can. |
| Below 1.5 mm | A dangerous defect in the UK MOT. Do not drive on these. |
Measure only the friction material, not the steel backing plate behind it. Exact limits vary by car and pad; your owner's manual or garage can tell you the figure for yours.
Step by step
- Park safely. Choose firm, level ground, put the handbrake on, and leave the car in gear or in Park. Let the brakes cool if you have just driven: discs get very hot.
- Turn the steering to full lock to see the front brakes more easily. The front wheels then angle out, which opens up the view behind the spokes.
- Find the caliper. Shine a torch through the wheel spokes. The caliper is the clamp that sits over the edge of the disc, usually towards the front or back of the wheel.
- Find the outer pad. Look at the edge of the caliper where it meets the disc. You will see the steel backing plate, then a layer of darker friction material pressed against the disc. That layer is what you are measuring.
- Judge the thickness. Compare it with the table above. A small ruler held near the pad helps you judge. If you are unsure, treat it as thin and have it measured.
- Look for uneven wear. If one end of the pad is much thinner than the other, or it is cracked, have a garage look: the caliper may be sticking.
- Look at the disc. Deep grooves, a raised lip at the outer edge, or blue heat marks mean the discs need checking too.
- Repeat on every wheel you can see. Note the readings, and put a reminder in our service tracker.
If the spokes are too narrow to see through, or you cannot see the pad clearly, do not guess. Ask a garage to check, which many do quickly when the car is in for any other work.
Taking the wheel off: read this first
To see the inner pad properly, the wheel has to come off. That means lifting the car, and that is where people get badly hurt.
Never put any part of your body under a car held up only by a jack. Jacks can slip or fail. Use axle stands (support stands) or ramps rated for your car's weight, on firm, level ground, at the lifting points in your owner's manual, and chock the wheels that stay on the ground. Check the car is stable on the stands before you go near it. If you do not have axle stands or are unsure, leave this check to a garage.
DIY or garage?
How to make your pads last longer
- Look further ahead and brake gently and early.
- Use a lower gear on long downhill stretches.
- Ask the garage to measure pad thickness at every service.
- Replace pads when they reach the limit, before they damage the discs. Read more in how long brake pads last.
Questions drivers ask
How thick should brake pads be?
Pads with about 3 mm (1/8 inch) of friction material or less are due for replacement. Many pad wear sensors trigger at around 2 mm. In the UK MOT, a pad worn below 1.5 mm is a dangerous defect. Your owner's manual or garage can give the exact minimum for your car.
Can I check brake pads without taking the wheel off?
Often, yes, if your wheels have wide enough spokes. You will usually only see the outer pad, though, and the inner pad does not always wear at the same rate. For a full check, a garage takes the wheels off.
How often should I check my brake pads?
A quick look every few months is easy, and a garage should check them at every service. Check sooner if you hear squealing or grinding, or a brake warning light comes on.
Do I need to check the rear pads too?
Yes. Front pads usually wear faster because they do most of the stopping, but rear pads wear too. Some cars have drum brakes at the back, which you cannot see without taking the drum off: leave those to a garage.
Sources
- GOV.UK: MOT inspection manual, section 1 (brakes) (accessed November 6, 2026)
- RAC: Car dashboard warning lights and what they mean (brake pad warning light) (accessed November 6, 2026)
- Stoneacre: What causes squeaky brakes? (accessed November 6, 2026)
- Carwow: How long do brake discs and pads last? (accessed November 6, 2026)
- Product Safety Australia (ACCC): Don't be a jackass with jacks (accessed November 6, 2026)
General information only. Every car is different: check your owner's manual, and if anything involves brakes, steering, tires or a burning smell, have a qualified mechanic look at it before you drive on.