Engineering • Machining • Workshop

The practical engineering platform.

35 dedicated calculators, engineering pages, worked examples, reference tables and straightforward guides built for real workshop and site tasks.

35dedicated calculators

14guides & references

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Formula-ledCore equations shown on calculator pages

Assumptions visibleInputs and limitations explained

No accountTools work without registration

Independent checkingCritical results should always be verified

Start with the task

What are you trying to do?

Use the guided routes to reach the right calculator, formula and supporting reference information.

1Tighten a bolt

Torque, preload, threads and clearance holes.

2Machine a component

RPM, surface speed, feed and drilling references.

3Estimate material

Plate, bar and pipe mass from real dimensions.

4Check an electrical load

Voltage drop, current and battery endurance.

Popular calculators

High-intent engineering tools.

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Fasteners

Bolt Torque Calculator

Estimate bolt tightening torque from preload, nominal diameter and nut factor.

Open calculator →Fasteners

Tap Drill Calculator

Estimate the tapping drill diameter for common metric threads.

Open calculator →Fasteners

Clearance Hole Calculator

Look up close, normal and loose metric bolt clearance-hole sizes.

Open calculator →Fasteners

Thread Pitch Calculator

Convert threads per inch to metric pitch, or metric pitch to TPI.

Open calculator →Materials

Steel Plate Weight Calculator

Calculate steel plate mass from length, width, thickness and density.

Open calculator →Materials

Round Bar Weight Calculator

Calculate the mass of solid round bar from diameter, length and density.

Open calculator →Materials

Pipe Weight Calculator

Estimate hollow circular pipe or tube mass from outside diameter and wall thickness.

Open calculator →Machining

Surface Speed Calculator

Calculate cutting surface speed from tool or workpiece diameter and RPM.

Open calculator →Machining

Spindle RPM Calculator

Calculate spindle RPM from cutting speed and tool or workpiece diameter.

Open calculator →

Workshop conversions

Common conversions in seconds.

Full toolbox

Conversion

N·m ↔ lbf·ft

Torque conversion for workshop specifications and tools.

Convert →Conversion

bar ↔ psi

Pressure conversion including kPa and MPa.

Convert →Conversion

mm ↔ inches

Fast metric and imperial dimensional conversion.

Convert →

Built for repeat use

Your workshop, one tap away.

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Keep useful answers and reopen the original tool.

≡Reference tables

Keep thread, drill and material data close.

35Full toolbox

Search every calculator and converter.

More everyday engineering

Quick answers for common jobs.

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Electrical

Ohm’s Law Calculator

Calculate voltage, current, resistance and power from two known electrical values.

Calculate →Mechanical

Pulley Speed Calculator

Calculate driven pulley speed from driver speed and pulley diameters.

Calculate →Mechanical

Cylinder Volume Calculator

Calculate cylindrical volume from diameter and length, with litres and cubic metres.

Calculate →Electrical

Electrical Power Calculator

Calculate DC electrical power, current or energy from voltage and current inputs.

Calculate →Conversions

Force Converter

Convert force between newtons, kilonewtons, kilogram-force and pounds-force.

Calculate →

Engineering hubs

Go deeper by discipline.

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Fasteners

Fasteners Engineering

Torque, threads, tapping and clearance-hole tools.

Explore hub →Machining

Machining

RPM, surface speed, feed and drill references.

Explore hub →Electrical

Electrical

Power, current, voltage drop and battery tools.

Explore hub →Hydraulics

Hydraulics & Fluid

Pressure, force, flow and pump calculations.

Explore hub →Materials

Materials & Fabrication

Weight, density and quantity estimation.

Explore hub →

Field guides

From answer to real-world decision.

Practical guides connect the calculator result to assumptions, checks and the next engineering step.

Fasteners

Bolt Torque Field Guide

Torque, preload, friction, lubrication and why published values vary.

Read field guide →Electrical

Motor Current Field Guide

Understand estimated current, efficiency, power factor and nameplate checks.

Read field guide →Machining

Speeds & Feeds Field Guide

Turn cutting data into a sensible starting point at the machine.

Read field guide →

Reference library

Tables and formulas worth bookmarking.

Metric and imperial thread data, drill charts, material densities, spanner sizes and core engineering formulas in a clean mobile-friendly library.

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Engineering Academy

Understand the calculation.

All guides

Fasteners

Understanding Bolt Preload

Why tightening torque is only an indirect way of controlling clamp force, and how friction changes the result.

Read guide →Machining

Choosing the Correct Cutting Speed

How work material, tool material, diameter and machine rigidity affect cutting speed.

Read guide →Fasteners

Metric and Imperial Threads Explained

A practical guide to diameter, pitch, TPI, thread form and identification.

Read guide →Materials

Material Density in Workshop Calculations

How density turns measured volume into a usable weight estimate.

Read guide →Mechanical

Hydraulic Pressure and Force Basics

How pressure, piston area, flow and efficiency relate in hydraulic systems.

Read guide →Electrical

Voltage Drop Explained Simply

Why cable length, current, material and cross-sectional area matter.

Read guide →