Bearing Life (L10) Calculator
SI
Imp
Imperial
Inputs
View results
Dynamic load rating C
(C)
Basic dynamic load rating from the bearing catalogue.
N
Equivalent load P
(P)
Equivalent dynamic bearing load (combine radial and axial loads separately, P = X·Fr + Y·Fa).
N
Speed
(n)
Operating speed.
rpm
Bearing type
Sets the load–life exponent p: 3 for ball bearings, 10/3 for roller bearings.
Ball bearing (p = 3)
Roller bearing (p = 10/3)
Results
Default result
Edit inputs
L10 life
(L₁₀)
216
million revolutions
Also computed
L10 life
(L₁₀ₕ)
2,400
hours
C/P ratio
(C/P)
Pass
6
(C/P)^p with p = 3 (ball bearing).
Method notes
3 notes
ISO 281 basic rating life L10 = (C/P)^p million revolutions; p = 3 for ball bearings, 10/3 for roller bearings.
Life in hours L10h = 10⁶ / (60·n) × (C/P)^p — divide the million-revolution life by the speed.
L10 is the life 90% of bearings reach (10% may fail by then). It excludes lubrication, temperature, contamination and the a₁/a₂₃/aISO modification factors of the modified rating life.
Powered by MachineCalcs ↗