Bearing Life Calculator
Calculate basic L10 rating life from dynamic load rating, equivalent bearing load, speed and bearing type.
Use the Bearing Life Calculator
Calculate basic L10 rating life from dynamic load rating, equivalent bearing load, speed and bearing type.
Calculations happen locally in your browser. ToolLott does not send these inputs to a server for this tool.
Preliminary engineering screening only. It does not replace project-specific design, applicable codes/standards, manufacturer data, transient/fatigue studies, geotechnical or site assessment, professional review or independent verification.
How to use it
Replace the worked-example values with actual project data. Review the intermediate quantities and visible assumptions before using the result elsewhere.
How the Bearing Life Calculator works
Calculate basic L10 rating life from dynamic load rating, equivalent bearing load, speed and bearing type. The methodology below exposes the production equation, a QA-verified worked example and the boundary between this screen and detailed design.
Calculation breakdown
ToolLott will explain the current inputs and displayed result here.
Basic bearing L10 rating life
The production engine evaluates L10 (million rev) = (C/P)^p; hours = L10 x 10^6 /(60 rpm). It begins by calculate C/P from the entered basic dynamic rating and equivalent load., then use exponent p=3 for ball bearings or 10/3 for roller bearings., and finally convert million revolutions to operating hours at the entered speed. This keeps the calculation auditable instead of hiding design assumptions behind a single number.
L10 (million rev) = (C/P)^p; hours = L10 x 10^6 /(60 rpm)ToolLott evaluates the relationship using the entered units and full numeric precision before display rounding.
| Symbol / input | Meaning | Unit |
|---|---|---|
dynamicRating | Dynamic load rating C (kN) | user input |
equivalentLoad | Equivalent bearing load P (kN) | user input |
rpm | Operating speed (rpm) | user input |
type | Bearing type | user input |
Step-by-step method
- Calculate C/P from the entered basic dynamic rating and equivalent load.
- Use exponent p=3 for ball bearings or 10/3 for roller bearings.
- Convert million revolutions to operating hours at the entered speed.
Worked example
Sofia, a project engineer, is comparing a bearing with 35 kN dynamic rating under a 12 kN equivalent load at 1,450 rpm.
Example inputs
- Dynamic load rating C (kN): 35
- Equivalent bearing load P (kN): 12
- Operating speed (rpm): 1450
- Bearing type: ball
Calculation / processing
C/P = 35 / 12 = 2.917; p = 3 for a ball bearing.L10 = 2.917³ = 24.812 million revolutions.Hours = 24.812e6 /(60 x 1450) = 285.2 h.
Use the result as a screening or quantity-planning value and compare it with the project criteria, manufacturer data and applicable engineering requirements before making a design or procurement decision.
Assumptions
- The entered values are representative of the condition being screened and use the units shown on the page.
- The equation models only the stated relationship; omitted system effects are not silently estimated.
Limitations
- This page is not engineering certification and does not replace applicable standards, design loads, manufacturer data, site investigation or competent professional review.
- Results can change materially when real geometry, losses, transients, material properties, duty cycles, safety factors or regulatory criteria differ from the simplified inputs.
Common questions
Is this a final engineering design?
No. It is a transparent screening calculation using the entered assumptions and the stated equation.
Why does the page show assumptions and limitations?
Engineering formulas are only valid within their modelling assumptions; exposing them helps users decide what additional design checks are required.
Should I use the rounded displayed value in later design work?
Use suitable calculation precision and the governing project/standard requirements rather than relying on display rounding alone.
Methodology sources
Related ToolLott tools
A realistic way Sofia could use this tool
Sofia is a project engineer.
Sofia is comparing a bearing with 35 kN dynamic rating under a 12 kN equivalent load at 1,450 rpm.
The scenario is tested with dynamic rating = 35; equivalent load = 12; rpm = 1450; type = “ball”. Those entries lead to Basic L10 life: 285.2 h. Because the inputs and result are both shown, Sofia can compare the example with real project/source data before reuse.
The worked result is Basic L10 life: 285.2 h; in this situation that lets Sofia calculate basic L10 rating life from dynamic load rating, equivalent bearing load, speed and bearing type. If the underlying values change, the example makes clear which inputs need to be updated rather than hiding the assumption. The page also keeps this limitation explicit: Preliminary screening/planning calculation only.
Fictional scenario using realistic example data. For Ready tools, the worked result is tied to the tested example shown in the tool. Replace the figures with your own inputs and independently verify important professional, financial, legal, health or safety decisions.
What this calculator is for
Use it to calculate basic L10 rating life from dynamic load rating, equivalent bearing load, speed and bearing type.
It sits within ToolLott’s Mechanical collection, where you can also calculate bearing life, belt length, gear ratio, power transmission, shaft checks, thermal expansion and torque.