Torque Unit Converter

How to use this calculator

What torque actually is

Torque is rotational force. It’s how hard something pushes in a circular direction rather than a straight line.

Hold a wrench on a bolt and push. The force you apply multiplied by the length of the wrench handle is the torque you’re delivering to the bolt. Double the wrench length, same force, double the torque. That’s why a longer breaker bar loosens stuck bolts that a short ratchet can’t move.

A torque wrench set to 100 N·m will click when you’ve applied 100 newtons of force at 1 meter of lever length, or 50 newtons at 2 meters, or 200 newtons at 0.5 meters. The rotational effect on the bolt is the same in all 3 cases.

The 5 torque units and how each one is built

Every torque unit combines a force unit with a distance unit. Change either component and you get a different unit. That’s why there are so many of them: different industries settled on different force and distance conventions.

Kilogram-force units use gravity to define force. 1 kgf is the force that Earth’s gravity exerts on a 1kg mass at standard gravity (9.80665 m/s²). That’s why kgf·m isn’t an SI unit: it bakes a gravitational constant into the force definition, which makes it technically dependent on location. For most practical purposes on Earth, this doesn’t matter.

Master conversion table: every unit to every other unit

This is the table worth bookmarking. Every row is a conversion factor: multiply your value in the left column’s unit by the factor to get the column header’s unit.

How to use this table: Find your source unit in the left column. Read across to the column for your target unit. Multiply.

Example: converting 250 lb·ft to N·m. Row = lb·ft, column = N·m. Factor = 1.355818. Answer: 250 × 1.355818 = 338.95 N·m.

The key conversion facts worth memorising

You won’t always have the calculator in front of you. These 4 relationships cover probably 90% of real-world torque conversions.

Conversion table: newton-meters to pound-feet (and back)

This is the conversion people search for most. Engine torque figures on manufacturer spec sheets usually appear in both N·m (for European markets) and lb·ft (for US/UK markets). Having both sides of the table means you can cross-check either way.

Conversion table: pound-feet to newton-meters

Reading a US vehicle spec sheet and need the metric torque setting? This table covers the range from small fasteners to heavy-duty applications.

Pound-inches: the unit for small fasteners

Pound-inches are 1/12 of a pound-foot. They show up whenever the torque values are small enough that expressing them in lb·ft would require awkward decimals like 0.42 lb·ft. Writing 5 lb·in is cleaner and less prone to misreading.

Kilogram-meters and kilogram-centimeters: the legacy units

kgf·m and kgf·cm aren’t SI units and haven’t been the standard for new technical publications for decades. But they show up in two places: older workshop manuals (particularly Japanese vehicles from the 1970s-2000s) and servo/motor specifications in robotics and automation.

Real-world torque specs: what the numbers look like in practice

A Formula 1 wheel nut is tightened to roughly 450 N·m (332 lb·ft) during a pitstop, in about 1.9 seconds. The pneumatic wheel gun delivering that torque is operating at approximately 3,500 RPM. Converting units is the least of the mechanic's problems, but they use N·m because F1 is run under FIA regulations that use SI units throughout.

The confusion between torque and energy

Newton-meters measure both torque and energy (joules). 1 joule = 1 newton-meter. But they’re measuring different things: torque is a rotational force (a vector with direction), energy is a scalar quantity.

In practice this distinction rarely causes problems because the context makes it obvious: if a spec sheet says 100 N·m for a fastener, it means torque. If a physics calculation gives you 100 N·m as a result of multiplying force by distance traveled, it means energy in joules.

Choosing the right torque wrench scale for your spec

Most torque wrenches come in either N·m or lb·ft. Some have dual scales. Before using the converter output, check which scale your wrench is calibrated in.

Common mistakes when converting torque

Confusing lb·ft with ft·lb. They’re the same unit. Some manuals write ft·lb instead of lb·ft. The order of the terms doesn’t change the meaning. 100 ft·lb = 100 lb·ft = 135.6 N·m.

Mixing up lb·ft and lb·in by a factor of 12. This one actually damages bolts. A spec for 20 lb·in misread as 20 lb·ft applies 12 times too much torque. On aluminium components or small fasteners, that strips threads or cracks housings. The converter output shows both units side by side specifically so you can catch this.

Using kgf·m when the manual means kg·cm. An older Japanese manual saying 8 kgf·m and another saying 80 kgf·cm are both about 78.5 N·m. But if you read 8 kgf·cm as 8 kgf·m, you apply 10 times the correct torque. Always confirm the unit suffix before converting.

Applying peak engine torque to fastener specs. An engine rated at 400 N·m produces that torque at the crankshaft. Fastener torque specs for that same engine’s bolts are completely different numbers. The output torque of the engine and the assembly torque of its fasteners are unrelated figures that just happen to use the same unit.