An avoirdupois ounce is 1/16 pound.
Ounces to Grains
Convert ounces (oz) to grains (gr) instantly. Free online weight converter with formulas, tables and examples.
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A grain is exactly 64.79891 milligrams.
gr = oz × 437.5
Results update instantly for Ounces to Grains conversions.
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Formula
gr = oz × 437.5
oz = gr ÷ 437.5
Conversion table
| 1 oz | 437.500000 gr |
| 5 oz | 2187.500000 gr |
| 10 oz | 4375.000000 gr |
| 20 oz | 8750.000000 gr |
| 50 oz | 21875.000000 gr |
| 100 oz | 43750.000000 gr |
| 500 oz | 218750.000000 gr |
| 1000 oz | 437500.000000 gr |
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Frequently asked questions
What is the source unit in this conversion?
The source unit is the ounce (oz). An avoirdupois ounce is 1/16 pound.
What is the destination unit in this conversion?
The destination unit is the grain (gr). A grain is exactly 64.79891 milligrams.
How do I convert ounces to grains?
Multiply the number of ounces by 437.5 to get the equivalent value in grains. For example, 5 oz × 437.5 = 2187.500000 gr.
Is the ounce to grain conversion exact?
Yes. This converter uses a fixed factor of 437.5, so results are precise and consistent every time you use it.
Where is this conversion commonly used?
It's used in everyday measurement, shipping and logistics, scientific and industrial work, and any context where you need to switch between ounce and grain values.
Can I convert grains back to ounces?
Yes. Multiply the grains value by 0.00228571428571, or divide it by 437.5, to convert back to ounces.
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About this conversion
This page converts ounces (oz) into grains (gr) using the Universal Converter's mass conversion engine.
Ounce-to-Grain conversions are useful for everyday calculations, scientific work, shipping, and any task that mixes different weight or mass units.
The formula is gr = oz × 437.5, based on the standard definitions of ounce and grain.
Because the conversion factor is fixed, results stay consistent and repeatable no matter how many times you calculate them.
Ounce: An avoirdupois ounce is 1/16 pound. Grain: A grain is exactly 64.79891 milligrams.