Practical calculation tools, right when you need them.

Calculation Tools for Mechatronics Engineers

We provide the technical calculations you need repeatedly in mechanical and electrical engineering, in a form that gives you instant results. Values are visualized in real time with animations and diagrams, so you can intuitively confirm what the numbers mean. All formulas follow JIS, ISO, and other industry standards.

Mechanical & Electrical

Covers fundamental calculations for mechanical design and power systems, including torque-RPM conversion and gear ratio analysis. Results are visualized with diagrams and animations.

Torque / Power / RPM CalculatorConvert between torque, power, and RPM for motor selection and drivetrain analysis. Includes unit conversion.Belt Length CalculatorDetermine belt length and wrap angles needed for belt replacement or layout design, from pulley diameters and center distance.Belt Speed CalculatorFind belt linear speed and driven RPM to verify speed ratios in belt drive systems.Engine Displacement CalculatorCalculate engine displacement in cc/L from bore, stroke, and cylinder count — a fundamental spec for registration and performance comparison.Gear Ratio & Spur GearCompute gear ratio, pitch circle diameter, center distance, and tooth forces for spur gear design.Spring CalculatorEstimate spring constant and deflection from material, wire diameter, and coil geometry to predict load-displacement behavior.

Machining

Calculate milling cutting conditions (fz, vf, n, Vc) from each other. Derive machining parameters directly from tool catalog values.

Milling fz CalculatorDerive feed per tooth (fz) — a key factor in tool life and surface finish — from spindle speed, table feed, and flute count.Milling vf CalculatorCalculate the table feed rate (vf) used for CNC F-value programming from fz, flute count, and spindle speed.Milling n CalculatorConvert a tool catalog's recommended cutting speed into spindle RPM. n = 1000Vc/(πD).Milling Vc CalculatorCheck whether current machining conditions fall within the tool's recommended range by back-calculating cutting speed. Vc = πDn/1000.

Electronics

Essential electronics calculations including resistor color code reading and LED circuit design. Values update in real time on circuit diagrams.

Resistor Color Code CalculatorIdentify resistor values instantly from color bands. Supports 4-, 5-, and 6-band resistors with tolerance display.LED Resistor CalculatorSize the current-limiting resistor to protect LEDs, calculated from supply voltage, forward voltage, and forward current.Ohm's Law CalculatorApply Ohm's law (V = IR) to find voltage, current, or resistance from two known values — a building block of circuit design.

Updates

  • 2026/04/05NewAdded milling machining calculator.
  • 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.