Practical calculation tools, right when you need them.

Calculation Tools for Mechatronics Engineers

Quick and accurate technical calculations for mechanical, electrical, and electronics engineering. Understand the meaning behind the numbers with animations.

TechCalcs is a collection of technical calculation tools for mechatronics engineers. From engine displacement and torque calculations to resistor values and Unix timestamp conversion — calculations you need repeatedly in mechanical, electrical, and electronics engineering, right in your browser. Formulas are implemented based on JIS/ISO and other industry standards, with reference equations and derivation sources documented within each tool.

Mechanical & Electrical

Engine Displacement CalculatorCalculate engine displacement in cc/L from bore, stroke, and number of cylinders.Torque / Power / RPM CalculatorConvert between torque, power, and RPM with built-in unit converters.Belt Length CalculatorCalculate open belt length and wrap angles from pulley diameters and center distance.Belt Speed CalculatorCalculate belt speed and driven RPM from pulley diameters and input RPM.Gear Ratio & Spur GearSpur gear design tool for gear ratio, pitch circle diameter, center distance, and force analysisSpring CalculatorCalculate spring constant and deflection for springs

Electronics

Resistor Color Code CalculatorRead resistor values and tolerances from color band codes.LED Resistor CalculatorCalculate the current-limiting resistor for LED circuits in real time.Ohm's Law CalculatorFind V, I, or R from two known values

Updates

  • 2026/04/03FixFixed an issue causing intermittent slow responses on some tools.
  • 2026/04/01NewAdded belt speed calculator.

Why TechCalcs?

Understand Results Visually

Go beyond raw numbers — grasp calculation results intuitively through animations and diagrams. Build an engineer's intuition for the physics behind the values.

Right-Sized Design

Focused on the calculations you actually need in the field. Not too complex, not too simplified — tools you can use immediately.

Commitment to Accuracy

Calculations are implemented based on JIS/ISO and other industry standards. Reference formulas and derivation sources are documented within each tool for full transparency.