The Torque Unit Decoder
Cordless tool torque specs are published in two different units, and the class determines which. Impact drivers use inch-pounds, impact wrenches use foot-pounds, and drills quote a low-speed peak. One foot-pound equals twelve inch-pounds, so a 400 ft-lb impact wrench is 4,800 in-lbs — roughly double even a strong impact driver.
The dataset
| Tool class | Unit published | What it measures | Typical range | Converted | Note | Source | Source class |
|---|---|---|---|---|---|---|---|
| Drill/driver | in-lbs | Peak torque at the low-speed (high-torque) gear | 300 - 1,200 in-lbs | 25 - 100 ft-lbs | Drills report their peak figure at low speed, where torque is highest and RPM lowest. | Manufacturer spec convention | standard/engineering reference |
| Impact driver | in-lbs | Peak rotational impact energy delivered to a 1/4-inch hex bit | 1,400 - 2,500 in-lbs | 117 - 208 ft-lbs | Impact drivers deliver torque in rapid rotational blows, not smooth continuous force. | Manufacturer spec convention | standard/engineering reference |
| Impact wrench | ft-lbs | Peak rotational impact energy delivered to a square drive | 100 - 1,000+ ft-lbs | 1,200 - 12,000+ in-lbs | Rated in ft-lbs because the figures are large; a 400 ft-lb wrench equals 4,800 in-lbs. | Manufacturer spec convention | standard/engineering reference |
| Hammer drill | in-lbs + BPM | Rotational torque plus blows per minute of percussive action | 500 - 900 in-lbs | 42 - 75 ft-lbs | The BPM figure describes percussion rate and is not comparable to torque at all. | Manufacturer spec convention | standard/engineering reference |
| Conversion rule | n/a | 1 ft-lb = 12 in-lbs | Divide in-lbs by 12 for ft-lbs | Multiply ft-lbs by 12 for in-lbs | The single conversion needed to compare any two tools whose specs use different units. | Unit definition | standard/engineering reference |
Download
torque-unit-decoder.csv (latest) · torque-unit-decoder-v1.0.csv (version-pinned, stable for citation)
License: CC BY 4.0 — free to use with attribution, including for commercial and machine-learning use.
How to cite
Torque Lab, “The Torque Unit Decoder”, version 1.0, 2026. Available at https://torque-lab.pages.dev/torque-unit-decoder/ under CC BY 4.0.
Methodology & versioning
- Conversion. 1 ft-lb = 12 in-lbs exactly. Converted ranges in this table are that arithmetic applied to the native range, and are labelled as such.
- Typical ranges describe the current mainstream market, not hard limits, and are drawn from published manufacturer specifications across platforms.
- BPM is not torque. A hammer drill's blows-per-minute figure describes percussion rate and cannot be compared against a torque number.
- We have not measured any tool. Every figure is a published specification or a stated unit conversion.
- Versioning. v1.0 published July 30, 2026. The version-pinned CSV will not change; corrections ship as a new version with a dated note here.
This is an equipment-specification reference. We report published manufacturer specifications and clearly-labelled unit conversions; we have not bench-tested any tool.