# Ounces to Pounds (oz to lb)

> Convert ounces to pounds: 1 oz = 0.0625 lb. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

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

## Formula

- `1 oz = 0.0625 lb`
- `pounds = ounces × 0.0625`
- Reverse: `ounces = pounds × 16`

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 oz = 0.3125 lb
- 12.5 oz = 0.78125 lb
- 100 oz = 6.25 lb

## Conversion table

| Ounces (oz) | Pounds (lb) |
| --- | --- |
| 1 | 0.0625 |
| 2 | 0.125 |
| 3 | 0.1875 |
| 4 | 0.25 |
| 5 | 0.3125 |
| 6 | 0.375 |
| 7 | 0.4375 |
| 8 | 0.5 |
| 9 | 0.5625 |
| 10 | 0.625 |
| 15 | 0.9375 |
| 20 | 1.25 |
| 25 | 1.5625 |
| 30 | 1.875 |
| 40 | 2.5 |
| 50 | 3.125 |
| 75 | 4.6875 |
| 100 | 6.25 |
| 200 | 12.5 |
| 250 | 15.625 |
| 500 | 31.25 |
| 1000 | 62.5 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=oz&to_unit=lb` → 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":"oz","to_unit":"lb"}`
- All mass units: https://tttkmbb.com/api/v1/units?quantity=mass · full converter: [Mass / Weight Converter](https://tttkmbb.com/conversion/mass.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**How many pounds are in one ounce?**

1 oz = 0.0625 lb. 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 ounces to pounds?**

Multiply the value in ounces by 0.0625: pounds = ounces × 0.0625. For example, 5 oz = 0.3125 lb.

**How do I convert pounds back to ounces?**

Multiply by the inverse factor 16 (ounces = pounds × 16), or use the pounds-to-ounces page.

## Related conversions

- [Pounds to ounces](https://tttkmbb.com/conversion/lbs-to-oz.md) (reverse)
- [Kilograms to Pounds](https://tttkmbb.com/conversion/kg-to-lbs.md)
- [Pounds to Kilograms](https://tttkmbb.com/conversion/lbs-to-kg.md)
- [Grams to Ounces](https://tttkmbb.com/conversion/grams-to-oz.md)
- [Ounces to Grams](https://tttkmbb.com/conversion/oz-to-grams.md)
- [Kilograms to Stone](https://tttkmbb.com/conversion/kg-to-stone.md)
- [Stone to Kilograms](https://tttkmbb.com/conversion/stone-to-kg.md)
- [Kilograms to Grams](https://tttkmbb.com/conversion/kg-to-grams.md)
- [Grams to Kilograms](https://tttkmbb.com/conversion/grams-to-kg.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)