# Pound-inches (in-lb) to Pound-feet (ft-lb) (lbf·in to lbf·ft)

> Convert pound-inches (in-lb) to pound-feet (ft-lb): 1 lbf·in = 0.0833333 lbf·ft. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

- Page id: `in-lbs-to-ft-lbs` · Quantity: Torque (`torque`, base unit Nm) · Tool: `convert_units`
- Canonical page: https://tttkmbb.com/conversion/in-lbs-to-ft-lbs · This document: https://tttkmbb.com/conversion/in-lbs-to-ft-lbs.md · JSON: https://tttkmbb.com/conversion/in-lbs-to-ft-lbs.json (add `?value=` for a result)

## Formula

- `1 lbf·in = 0.0833333 lbf·ft`
- `pound-feet (ft-lb) = pound-inches (in-lb) × 0.08333333333`
- Reverse: `pound-inches (in-lb) = pound-feet (ft-lb) × 12`

The factor follows from the SI definitions of both units (NIST SP 811); values below are rounded to 6 significant figures, the API returns up to 12.

## Worked examples

- 5 lbf·in = 0.416667 lbf·ft
- 12.5 lbf·in = 1.04167 lbf·ft
- 100 lbf·in = 8.33333 lbf·ft

## Conversion table

| Pound-inches (in-lb) (lbf·in) | Pound-feet (ft-lb) (lbf·ft) |
| --- | --- |
| 1 | 0.0833333 |
| 2 | 0.166667 |
| 3 | 0.25 |
| 4 | 0.333333 |
| 5 | 0.416667 |
| 6 | 0.5 |
| 7 | 0.583333 |
| 8 | 0.666667 |
| 9 | 0.75 |
| 10 | 0.833333 |
| 15 | 1.25 |
| 20 | 1.66667 |
| 25 | 2.08333 |
| 30 | 2.5 |
| 40 | 3.33333 |
| 50 | 4.16667 |
| 75 | 6.25 |
| 100 | 8.33333 |
| 200 | 16.6667 |
| 250 | 20.8333 |
| 500 | 41.6667 |
| 1000 | 83.3333 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=lbf_in&to_unit=lbf_ft` → unified JSON envelope with `result.values.result`, `formula`, `factor`, `sources`, `freshness`
- MCP: server `https://tttkmbb.com/mcp`, tool `convert_units` with `{"value":5,"from_unit":"lbf_in","to_unit":"lbf_ft"}`
- All torque units: https://tttkmbb.com/api/v1/units?quantity=torque · full converter: [Torque Converter](https://tttkmbb.com/conversion/torque.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**How many pound-feet (ft-lb) are in one pound-inch?**

1 lbf·in = 0.0833333 lbf·ft. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

**What is the formula to convert pound-inches (in-lb) to pound-feet (ft-lb)?**

Multiply the value in pound-inches (in-lb) by 0.08333333333: pound-feet (ft-lb) = pound-inches (in-lb) × 0.08333333333. For example, 5 lbf·in = 0.416667 lbf·ft.

**How do I convert pound-feet (ft-lb) back to pound-inches (in-lb)?**

Multiply by the inverse factor 12 (pound-inches (in-lb) = pound-feet (ft-lb) × 12), or use the pound-feet (ft-lb)-to-pound-inches (in-lb) page.

## Related conversions

- [Pound-feet (ft-lb) to pound-inches (in-lb)](https://tttkmbb.com/conversion/ft-lbs-to-in-lbs.md) (reverse)
- [Newton-meters to Pound-feet (ft-lb)](https://tttkmbb.com/conversion/newton-meters-to-ft-lbs.md)
- [Pound-feet (ft-lb) to Newton-meters](https://tttkmbb.com/conversion/ft-lbs-to-newton-meters.md)
- [Newton-meters to Pound-inches (in-lb)](https://tttkmbb.com/conversion/newton-meters-to-in-lbs.md)
- [Pound-inches (in-lb) to Newton-meters](https://tttkmbb.com/conversion/in-lbs-to-newton-meters.md)
- [Newton-meters to Kilogram-force meters](https://tttkmbb.com/conversion/newton-meters-to-kgf-m.md)
- [Kilogram-force meters to Newton-meters](https://tttkmbb.com/conversion/kgf-m-to-newton-meters.md)
- [Kilogram-force meters to Pound-feet (ft-lb)](https://tttkmbb.com/conversion/kgf-m-to-ft-lbs.md)
- [Pound-feet (ft-lb) to Kilogram-force meters](https://tttkmbb.com/conversion/ft-lbs-to-kgf-m.md)

## Data Sources

- NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors — https://www.nist.gov/pml/special-publication-811 (standard, retrieved 2026-09-24)
- BIPM – The International System of Units (SI Brochure, 9th edition) — https://www.bipm.org/en/publications/si-brochure (standard, retrieved 2026-09-24)
- Wikipedia – Conversion of units — https://en.wikipedia.org/wiki/Conversion_of_units (reference, retrieved 2026-09-24)