Bearings
Bearing L10 Life Calculator
Basic rating life of rolling bearings per ISO 281: L10 in millions of revolutions and hours, with a target-life comparison.
Parameters
Results
- Basic rating life (L10)(L10)
- 2097.15 Mrev
- Basic rating life (L10h)(L10h)
- 24966 h
- Life vs target(L10h/target)
- 1.25
Design checks
- [PASS] P = 1 kN below C = 12.8 kN — L10 is meaningfuldynamic_overload
- [PASS] L10h = 24966.1 h meets the target life of 20000 htarget_life_check
Formulas
L10 = (C/P)^p — basic rating life in millions of revolutions= 2097.15
Expression: (dynamicLoadRating / equivalentLoad)^bearingType
L10h = 10⁶·L10 / (60·n)= 24966.1
Expression: 1000000 * l10MillionRevs / (60 * speed)
60 — minutes per hour (n is in rpm)
1000000 — millions of revolutions → revolutions
L10h / target — above 1 the basic rating life meets the reference target= 1.24830
Expression: l10Hours / targetLife
Results are for preliminary design. Verify before manufacturing.
Export
STEP export runs entirely in your browser; the geometry kernel downloads once on first export.
How the bearing L10 life calculator works
ISO 281 defines the basic rating life L10 as the number of millions of revolutions that 90% of a group of identical bearings will reach before material fatigue spalls the raceways. It follows L10 = (C/P)^p, where C is the basic dynamic load rating from the catalogue, P the equivalent dynamic load (P = X·V·Fr + Y·Fa combines the radial and axial components), and p the life exponent: 3 for ball bearings (deep groove, angular contact) and 10/3 for roller bearings (cylindrical, tapered). Because of that exponent, life is extremely sensitive to load — halving P multiplies ball-bearing life by eight. In hours, L10h = 10⁶·L10/(60·n) converts the revolution count at n rpm into running time.
The output also compares L10h against a reference target (20,000 h is a common machine-building value — adjust it to your industry). Note the scope: L10 is a fatigue-life calculation and only meaningful while P stays below C. When the equivalent load reaches the dynamic load rating the contact is overloaded — the calculator flags this explicitly as invalid — and a static (C₀) check governs instead. Real service life also depends on lubrication, contamination and mounting accuracy; the ISO 281 modification factor Lnm = a₁·aISO·L10 covers those effects and is outside the scope of this calculator.
Need the shaft it spins on? The bolt preload torque calculator covers the fasteners around it.