Ounce to Grain Converter
Convert between ounces and grains instantly with our accurate weight conversion tool. Supports whole numbers, decimals, and fractions.
Understanding Ounces and Grains
Our Ounce to Grain converter provides instant, accurate conversions between these two units of weight measurement. Whether you’re working with precious metals, reloading ammunition, or dealing with small weight measurements in scientific applications, this tool simplifies your calculations.
What is an Ounce?
An ounce (abbreviated as “oz”) is a unit of weight used in the imperial and US customary systems. There are two main types of ounces:
- Avoirdupois ounce: The most common ounce, equal to 1/16 of a pound or approximately 28.3495 grams
- Troy ounce: Used for precious metals, equal to approximately 31.1035 grams
Our converter uses the avoirdupois ounce (the standard ounce) for calculations.
What is a Grain?
A grain (abbreviated as “gr”) is a small unit of weight originally based on the weight of a single grain of cereal. In the avoirdupois, troy, and apothecaries’ systems, one grain is equal to exactly 64.79891 milligrams.
Grains are commonly used in:
- Reloading ammunition and firearm projectile measurements
- Jewelry and precious metals
- Pharmaceutical measurements
Conversion Formula
The conversion between ounces and grains is straightforward:
1 ounce (oz) = 437.5 grains (gr)
1 grain (gr) = 0.00228571 ounces (oz)
Common Ounce to Grain Conversions
| Ounces (oz) | Grains (gr) |
|---|---|
| 0.1 oz | 43.75 gr |
| 0.25 oz | 109.375 gr |
| 0.5 oz | 218.75 gr |
| 1 oz | 437.5 gr |
| 2 oz | 875 gr |
| 5 oz | 2,187.5 gr |
| 10 oz | 4,375 gr |
How to Use the Ounce to Grain Converter
Using our converter is simple:
- Enter your value in the “From” field (supports whole numbers, decimals like 0.5, or fractions like 1 1/4)
- Select your input unit (default is ounces)
- The conversion will happen automatically
- Click the swap button (⇄) to reverse the conversion direction
Practical Applications
Understanding ounce to grain conversions is essential for:
- Ammunition reloading: Powder charges are often measured in grains
- Jewelry making: Precious metal weights may be measured in grains
- Medicine: Some medications use grain measurements
- Scientific research: Precise small weight measurements