MechClarity · Free reference tools
Mechanical Engineering Calculators
Calculate gear geometry, shaft stress, bearing life, belt and chain length, bolt preload, and shaft power in your browser. Choose from 37 focused tools with unit selectors, worked examples, source notes, and explicit model limits.
Find a tool for your engineering task
7 tools
Gear Calculators: Ratio, Module, Dimensions & Forces
Calculate gear ratio, module and diametral pitch, spur gear dimensions, center distance, mesh forces, backlash, and simple planetary speeds.
12 tools
Shaft Calculators: Stress, Deflection & Critical Speed
Calculate shaft torsion, diameter, bending stress, bearing reactions, deflection, critical speed, key stress, and rigid flange coupling loads.
6 tools
Bearing Calculators: L10 Life, Loads & Static Safety
Calculate bearing L10 life, equivalent dynamic and static loads, required dynamic rating, static safety factor, and variable-duty equivalent load.
4 tools
Belt & Pulley Calculators: Length, Speed & Ratio
Calculate V-belt datum length, timing-belt pitch length and tooth count, pulley speed ratio, belt speed, or pulley RPM with explicit diameter conventions.
1 tool
Roller Chain Calculator: Links & Center Distance
Estimate roller-chain length and whole link count for an open two-sprocket drive, then check the center distance after choosing a link count.
6 tools
Bolt Calculators: Torque, Preload & Joint Stiffness
Estimate bolt torque and preload, bolt and clamped-member stiffness, external load sharing, joint separation, and thermal preload change.
1 tool
Power, Torque & RPM Calculator and Drive Tools
Convert between shaft power, torque, and rotational speed in SI or imperial units, then continue to gear, pulley, shaft, and bearing calculations.
Start with a specific calculation
- Reference calculator #001
Gear Center Distance Calculator
Calculate the nominal center distance, pitch diameters, and ratio of two standard external spur gears from module and tooth counts.
- Reference calculator #004
RPM / Torque / Power Calculator
Calculate steady mechanical shaft power, torque, or RPM from the other two quantities, with metric and imperial unit conversion.
- Reference calculator #014
Bearing L10 Basic Rating Life Calculator
Calculate ISO 281 bearing L10 basic rating life in millions of revolutions, total revolutions, hours, days, or years from C, P, speed, and bearing type.
What can you check with these calculators?
Use MechClarity to explore a defined calculation, compare input cases, and check a result against the displayed equations. Each tool keeps its assumptions and exclusions visible. For example, gear ratio answers a speed question, while gear mesh force starts with a known torque and pitch diameter. Those are different tasks with different input requirements.
How should you use an engineering result?
- Choose the tool whose arrangement and assumptions match the problem.
- Enter the required quantities with their units and verify any catalog factors, material properties, or allowable values.
- Compare the result with the worked example and formula explanation, then read the displayed warnings.
- Complete the remaining application, safety, strength, and manufacturer checks before making a design decision.
Are the tools free, and do they require an account?
The calculators are free to use and run in your browser without an account. A shared calculation URL may contain the entered values, so review it before sharing. The calculator directory lists every available tool by category.
Where do the formulas and assumptions come from?
Each tool provides its own reference list and explains how the cited material relates to the calculation. References include manufacturer technical manuals, standards context, engineering publications, and unit definitions. Read the calculation methodology and source policy for the distinction between a reference result, a software check, and engineering approval.