# Pounds per cubic foot to Kilograms per cubic meter (lb/ft³ to kg/m³)

> Convert pounds per cubic foot to kilograms per cubic meter: 1 lb/ft³ = 16.0185 kg/m³. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

- Page id: `lb-per-ft3-to-kg-per-m3` · Quantity: Density (`density`, base unit kg/m3) · Tool: `convert_units`
- Canonical page: https://tttkmbb.com/conversion/lb-per-ft3-to-kg-per-m3 · This document: https://tttkmbb.com/conversion/lb-per-ft3-to-kg-per-m3.md · JSON: https://tttkmbb.com/conversion/lb-per-ft3-to-kg-per-m3.json (add `?value=` for a result)

## Formula

- `1 lb/ft³ = 16.0185 kg/m³`
- `kilograms per cubic meter = pounds per cubic foot × 16.01846337`
- Reverse: `pounds per cubic foot = kilograms per cubic meter × 0.06242796058`

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 lb/ft³ = 80.0923 kg/m³
- 12.5 lb/ft³ = 200.231 kg/m³
- 100 lb/ft³ = 1601.85 kg/m³

## Conversion table

| Pounds per cubic foot (lb/ft³) | Kilograms per cubic meter (kg/m³) |
| --- | --- |
| 1 | 16.0185 |
| 2 | 32.0369 |
| 3 | 48.0554 |
| 4 | 64.0739 |
| 5 | 80.0923 |
| 6 | 96.1108 |
| 7 | 112.129 |
| 8 | 128.148 |
| 9 | 144.166 |
| 10 | 160.185 |
| 15 | 240.277 |
| 20 | 320.369 |
| 25 | 400.462 |
| 30 | 480.554 |
| 40 | 640.739 |
| 50 | 800.923 |
| 75 | 1201.38 |
| 100 | 1601.85 |
| 200 | 3203.69 |
| 250 | 4004.62 |
| 500 | 8009.23 |
| 1000 | 16018.5 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=lb%2Fft3&to_unit=kg%2Fm3` → 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":"lb/ft3","to_unit":"kg/m3"}`
- All density units: https://tttkmbb.com/api/v1/units?quantity=density · full converter: [Density Converter](https://tttkmbb.com/conversion/density.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**How many kilograms per cubic meter are in one pound per cubic foot?**

1 lb/ft³ = 16.0185 kg/m³. 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 pounds per cubic foot to kilograms per cubic meter?**

Multiply the value in pounds per cubic foot by 16.01846337: kilograms per cubic meter = pounds per cubic foot × 16.01846337. For example, 5 lb/ft³ = 80.0923 kg/m³.

**How do I convert kilograms per cubic meter back to pounds per cubic foot?**

Multiply by the inverse factor 0.06242796058 (pounds per cubic foot = kilograms per cubic meter × 0.06242796058), or use the kilograms per cubic meter-to-pounds per cubic foot page.

## Related conversions

- [Kilograms per cubic meter to pounds per cubic foot](https://tttkmbb.com/conversion/kg-per-m3-to-lb-per-ft3.md) (reverse)
- [Kilograms per cubic meter to Grams per cubic centimeter](https://tttkmbb.com/conversion/kg-per-m3-to-g-per-cm3.md)
- [Grams per cubic centimeter to Kilograms per cubic meter](https://tttkmbb.com/conversion/g-per-cm3-to-kg-per-m3.md)
- [Grams per milliliter to Kilograms per cubic meter](https://tttkmbb.com/conversion/g-per-ml-to-kg-per-m3.md)
- [Kilograms per cubic meter to Grams per milliliter](https://tttkmbb.com/conversion/kg-per-m3-to-g-per-ml.md)
- [Pounds per US gallon to Kilograms per liter](https://tttkmbb.com/conversion/lb-per-gallon-to-kg-per-liter.md)
- [Kilograms per liter to Pounds per US gallon](https://tttkmbb.com/conversion/kg-per-liter-to-lb-per-gallon.md)
- [Grams per cubic centimeter to Pounds per cubic inch](https://tttkmbb.com/conversion/g-per-cm3-to-lb-per-in3.md)
- [Pounds per cubic inch to Grams per cubic centimeter](https://tttkmbb.com/conversion/lb-per-in3-to-g-per-cm3.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)