Metric and Imperial Conversion Calculator – Fast & Accurate Unit Conversions
Our metric and imperial conversion calculator lets you quickly convert everyday measurements used in DIY, engineering, and workshop tasks. Instantly switch between metric and imperial units such as mm to inches, kg to lb, litres to gallons, bar to psi, and °C to °F. Fast, accurate conversions on mobile or desktop.
What This Metric and Imperial Conversion Calculator Covers
This metric and imperial conversion calculator includes the most commonly used measurement categories so you can convert values quickly without searching for charts or formulas. The calculator uses standard SI relationships for accuracy and provides reliable results for everyday conversions.
- Length: mm, cm, m, km ↔ in, ft, yd, mi (e.g., mm to inches, metres to feet)
- Area: m², cm², mm², hectare ↔ in², ft², yd², acre
- Volume: ml, L, m³ ↔ in³, ft³, yd³, UK gallons and US gallons
- Mass: mg, g, kg, tonne ↔ oz, lb, st
- Speed: m/s, km/h ↔ mph, ft/s, knot
- Pressure: Pa, kPa, MPa, bar, atm ↔ psi
- Energy & Power: J, kJ, MJ, Wh, kWh, cal, BTU; W, kW ↔ hp
- Torque & Angle: N·m ↔ lbf·ft / lbf·in; degrees, radians, gradians
- Temperature: Celsius ↔ Fahrenheit ↔ Kelvin
How to Use the Conversion Calculator
- Select the measurement category such as Length, Pressure, or Temperature.
- Choose the units to convert — for example mm to inches or bar to psi.
- Enter your value to see the result instantly.
- Use the swap option to reverse the conversion direction.
Why Use This Metric and Imperial Conversion Calculator?
Accuracy, speed, and simplicity. This tool keeps everything on a single screen so you can convert measurements quickly while working on a project. Clear unit labels reduce confusion between UK and US measurements, and the responsive layout works well on phones and tablets for use on-site or in the workshop. Whether you are checking a drill size in mm to inches, converting bar to psi for air tools, or comparing kilowatts to horsepower, this calculator provides reliable results instantly.
Common Conversion Examples
- Length: 25 mm → inches, 3 m → feet
- Mass: 10 kg → pounds
- Volume: 5 L → UK gallons
- Pressure: 2.5 bar → psi
- Temperature: 20 °C → °F
- Power: 2.2 kW → hp
- Torque: 120 N·m → lbf·ft
Notes
- Temperature conversions between °C, °F, and K use exact formulas.
- All other conversions follow standard SI unit relationships.
- Always check whether a specification refers to a UK gallon or US gallon before ordering parts or materials.
From metric to imperial or imperial to metric, this practical calculator helps you convert measurements quickly and accurately — ideal for DIY projects, engineering work, workshop calculations, and technical study.
Unit Conversion Calculator
Convert common DIY and trade units.
Result
Tips
- Use the ⇄ button to swap units.
- Temperature converts exactly (°C, °F, K). Other categories use SI base conversions.
