Bearing Life (L10) Calculator
Basic rating life of a rolling bearing in hours, revolutions and years of continuous running.
Results
Bearing life
1437
h
Revolutions
125.00
×10⁶
Years
0.16
What this tool does
Life falls with the cube of the load, so a bearing carrying 25 % less load lasts more than twice as long. Use exponent 3 for ball bearings and 10/3 for roller bearings, and take the dynamic load rating C straight from the manufacturer's table.
Formula
L₁₀ = (C ÷ P)^p × 10⁶ revolutions (p = 3 for ball bearings)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
c | Dynamic load rating C | kN |
p | Equivalent load P | kN |
n | Rotational speed | rpm |
ex | Value | — |
H | Bearing life | h |
R | Revolutions | ×10⁶ |
Y | Years | — |
Worked example
- Dynamic load rating C25 kN
- Equivalent load P5 kN
- Rotational speed1450 rpm
- Value3
- Bearing life1437 h
- Revolutions125.00 ×10⁶
- Years0.16
Limitations
- For work that must comply with a standard or be signed off, check the result against the applicable code and have it reviewed by a qualified engineer.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.
- The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.
Frequently asked questions
What does L10 actually promise?
That 90 % of a large batch of identical bearings will still be running after that many hours, under the assumed load and with proper lubrication. It is a statistical figure, not a guarantee for your particular bearing: one in ten is expected to fail sooner. Poor lubrication, misalignment and contamination shorten real life far more than load does.