---
title: "Ounces to Grains — oz to gr converter"
description: "1 ounce = 437.5 grains. Convert ounces to grains with a full conversion table, the exact formula, and a calculator for any value."
url: https://atoneplace.net/convert/oz-to-grains/
site: "At One Place"
---

# Ounces to grains

**1 ounce in grains: 1 oz = 437.5 gr**

gr = oz × 437.5

To convert ounces to grains, multiply by 437.5. The table below gives the values people look up most often, and the converter works for any number.

## Ounces to grains table

*Common ounce values converted to grains.*

| Ounces | Grains |
| --- | --- |
| 1 oz | 437.5 |
| 2 oz | 875 |
| 3 oz | 1,312.5 |
| 4 oz | 1,750 |
| 5 oz | 2,187.5 |
| 10 oz | 4,375 |
| 15 oz | 6,562.5 |
| 20 oz | 8,750 |
| 25 oz | 10,937.5 |
| 30 oz | 13,125 |
| 40 oz | 17,500 |
| 50 oz | 21,875 |
| 75 oz | 32,812.5 |
| 100 oz | 43,750 |
| 250 oz | 109,375 |
| 500 oz | 218,750 |
| 1,000 oz | 437,500 |

## How the conversion works

The relationship is gr = oz × 437.5. Both units measure mass, so the conversion is a fixed factor that never changes. The figure is exact rather than approximate: since the international yard and pound agreement of 1959, an inch is defined as exactly 25.4 millimetres and a pound as exactly 0.45359237 kilograms, and every other imperial and US customary unit here is derived from those two.

## Common questions

### How many grains are in one ounce?

One ounce equals 437.5 grains. gr = oz × 437.5.

### How do you convert ounces to grains?

Use gr = oz × 437.5. So 10 oz is 4,375 gr.

### How many ounces are in one grain?

One grain equals 0.0022857 ounces, which is the reverse of the conversion above.

## Related pages

- [Grains to Ounces](https://atoneplace.net/convert/grains-to-oz/)
- [Ounces to Kilograms](https://atoneplace.net/convert/oz-to-kg/)
- [Ounces to Grams](https://atoneplace.net/convert/oz-to-grams/)
- [Ounces to Milligrams](https://atoneplace.net/convert/oz-to-mg/)
- [Ounces to Tonnes](https://atoneplace.net/convert/oz-to-tonnes/)
- [Ounces to Pounds](https://atoneplace.net/convert/oz-to-lbs/)
- [Ounces to Stone](https://atoneplace.net/convert/oz-to-stone/)

## Sources

- Guide for the Use of the International System of Units (SP 811) — NIST (https://www.nist.gov/pml/special-publication-811) [Public domain (US Government)]
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (https://www.bipm.org/en/publications/si-brochure)
- Calculated on this page — At One Place (/about/)