About
What these calculators compute, and which standards they follow.
What this site provides
OilHive provides tribology calculators for viscosity, film thickness, and wear — the calculations that come up mid-way through a design or an experiment, in a form you can run on the spot.
There is no shortage of tribology calculators online, but most of them disclaim their way out of showing the equation or its valid range. That makes the result unusable in a paper or a QC report. Every calculator here states the equation it uses, the standard it follows, the definition and unit of each variable, and the range over which it is valid. You should not have to take the number on trust — you should be able to reproduce it.
What happens to your inputs
All calculations run entirely in your browser. The values you type and the surface data you load are never sent to a server, and the PDF calculation record is generated in the browser as well.
The calculators and their standards
- Oil Blend Viscosity CalculatorASTM D341 · Refutas
- Viscosity Index & Temperature CalculatorASTM D2270 · ISO 2909 · ASTM D341
- Lambda Ratio CalculatorHamrock–Dowson · Hertz
- Stribeck Curve CalculatorStribeck
- Specific Wear Rate CalculatorArchard · ASTM G99
Viscosity–temperature behaviour follows ASTM D341, viscosity index follows ASTM D2270 / ISO 2909, and the wear-test conventions follow ASTM G99. Each tool page shows the equation it actually evaluates.
How to treat the results
The values here are reference figures derived from published equations and standards. Real lubrication depends on the oil, its additives, the temperature distribution, the surface condition, and the operating duty — any of which can fall outside a model's assumptions. Before committing a design, accepting or rejecting a part, or setting a maintenance interval, confirm the result with measurement.
Contact
Corrections to the equations, or tools you would like added:
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