Brake Pad Life Calculator
Miles left on your pads and cost per mile.
Enter your values
Enter the pad thickness when new in mm.
Enter the current pad thickness in mm.
Enter the miles on these pads in mi.
Enter the miles per month in mi.
Enter the cost of a pad and rotor job in $.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Miles remaining
- 20,000 mi
- Months remaining
- 20 months
- Wear rate
- 0.2 mm per 1,000 mi
- Expected total pad life
- 45,000 mi
- Brake cost per mile
- $0.01
- Status
- Serviceable
Quick answer
Pad wear is roughly linear with mileage, so remaining life = usable material above 3 mm ÷ wear per 1,000 miles.
Miles left = (current − 3 mm) ÷ wear rate
At a glance
| What it does | Miles left on your pads and cost per mile. |
|---|---|
| Category | Auto |
| Inputs needed | Pad thickness when new, Current pad thickness, Miles on these pads, Miles per month, Cost of a pad and rotor job |
| Main output | Miles remaining |
| Formula | Miles left = (current − 3 mm) ÷ wear rate |
| Cost | Free — no sign-up, no download |
How to use the Brake Pad Life Calculator
- 1Measure the friction material, not the backing plate.
- 2Enter the miles covered since the pads were fitted.
- 3Enter your monthly mileage and typical job cost.
Inputs explained
- Pad thickness when new(mm)
- Enter the pad thickness when new in mm.
- Current pad thickness(mm)
- Enter the current pad thickness in mm.
- Miles on these pads(mi)
- Enter the miles on these pads in mi.
- Miles per month(mi)
- Enter the miles per month in mi.
- Cost of a pad and rotor job($)
- Enter the cost of a pad and rotor job in $.
Worked example
Using the values the calculator loads with:
Inputs
- Pad thickness when new12 mm
- Current pad thickness7 mm
- Miles on these pads25000 mi
- Miles per month1000 mi
- Cost of a pad and rotor job450 $
Results
- Miles remaining20,000 mi
- Months remaining20 months
- Wear rate0.2 mm per 1,000 mi
- Expected total pad life45,000 mi
- Brake cost per mile$0.01
- StatusServiceable
Frequently asked questions
At what thickness must pads be replaced?
Below 3 mm of friction material most manufacturers call the pad worn out, and squealer tabs usually start to sound around 3–4 mm.
Why do front pads wear faster?
Weight transfers forward under braking, so front brakes do roughly 70% of the work and typically last half as long as the rears.
What do I need to enter into the Brake Pad Life Calculator?
Just 5 values: pad thickness when new, current pad thickness, miles on these pads, miles per month, cost of a pad and rotor job. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Brake Pad Life Calculator work out the answer?
Pad wear is roughly linear with mileage, so remaining life = usable material above 3 mm ÷ wear per 1,000 miles. It applies the formula Miles left = (current − 3 mm) ÷ wear rate and shows the working so you can check each step by hand.
Is the Brake Pad Life Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.