Ounce to Grain Converter
Enter the value that you want to convert ounce (oz) to grain (gr) or grain to ounce.Also written as OZ to GR conversion.
1 ounce = 437.5000000 grain
Formula: grain = ounce value × 437.5000000
OZ to GR — ounce to grain
10 ounce = 4375.00000 grain
Popular Weight Converters:
How Ounce Relates to Grain
The Ounce Explained
Ounce (oz) is a unit of weight measurement. 1 ounce is equal to 437.5000000 grain.
The Grain Explained
Grain (gr) is a unit of weight measurement. 1 grain is equal to 0.0022857 ounce.
Understanding Weight Conversions
Weight unit conversions are among the most frequently performed in daily life. International commerce ships in metric tonnes and kilograms, while US domestic logistics uses pounds and ounces. Recipes from different countries use different systems — a European cake recipe in grams versus an American one in cups and ounces. Pharmacists convert between milligrams and grains for medication dosing. Athletes track body weight across metric and imperial systems depending on their country and sport federation requirements.
ounce to grain metric conversion table
| 0.01 oz | = | 4.37500 gr |
| 0.1 oz | = | 43.75000 gr |
| 1 oz | = | 437.50000 gr |
| 2 oz | = | 875.00000 gr |
| 3 oz | = | 1312.50000 gr |
| 4 oz | = | 1750.00000 gr |
| 5 oz | = | 2187.50000 gr |
| 6 oz | = | 2625.00000 gr |
| 7 oz | = | 3062.50000 gr |
| 8 oz | = | 3500.00000 gr |
| 9 oz | = | 3937.50000 gr |
| 10 oz | = | 4375.00000 gr |
| 11 oz | = | 4812.50000 gr |
| 12 oz | = | 5250.00000 gr |
| 13 oz | = | 5687.50000 gr |
| 14 oz | = | 6125.00000 gr |
| 15 oz | = | 6562.50000 gr |
| 16 oz | = | 7000.00000 gr |
| 17 oz | = | 7437.50000 gr |
| 18 oz | = | 7875.00000 gr |
| 19 oz | = | 8312.50000 gr |
| 20 oz | = | 8750.00000 gr |
| 30 oz | = | 13125.00000 gr |
| 40 oz | = | 17500.00000 gr |
| 50 oz | = | 21875.00000 gr |
| 60 oz | = | 26250.00000 gr |
| 70 oz | = | 30625.00000 gr |
| 80 oz | = | 35000.00000 gr |
| 90 oz | = | 39375.00000 gr |
| 100 oz | = | 43750.00000 gr |
| 200 oz | = | 87500.00000 gr |
| 300 oz | = | 131250.00000 gr |
| 400 oz | = | 175000.00000 gr |
| 500 oz | = | 218750.00000 gr |
| 600 oz | = | 262500.00000 gr |
| 700 oz | = | 306250.00000 gr |
| 800 oz | = | 350000.00000 gr |
| 900 oz | = | 393750.00000 gr |
| 1000 oz | = | 437500.00000 gr |
How to Convert OZ to GR (Ounce to Grain)?
We can convert ounce to grain by using an example.
Example:
Convert 20 Ounce to Grain?
We know 1 Ounce = 437.5000000 grain; 1 Grain = 0.0022857 ounce.
20 ounce = ___gr
20 × 437.5000000 = 8750.00000 gr (we know 1 ounce = 437.5000000 grain)
Answer:
20 ounce = 8750.00000 grain
How to Convert Ounces to Grains (Step-by-Step)
One avoirdupois ounce equals exactly 437.5 grains. This conversion is used in ammunition reloading, archery (arrow weight), and traditional pharmacy. The relationship is exact because both are defined within the avoirdupois system.
- Identify the weight in ounces (oz) you want to convert.
- Multiply by 437.5 to get the value in grains.
- This is an exact conversion within the avoirdupois system.
Common Ounces to Grains Conversions
Reference values for ammunition, archery, and precision measurements.
| Ounce | Grain |
|---|---|
| 0.1 oz | 43.75 grains |
| 0.25 oz | 109.375 grains |
| 0.5 oz | 218.75 grains |
| 1 oz | 437.5 grains |
| 2 oz | 875 grains |
| 4 oz | 1,750 grains |
| 8 oz | 3,500 grains |
Solved Examples: Ounces to Grains
Question 1: A shotgun shell lists a payload of 1⅛ oz. How many grains of shot?
Solution:
Weight in grains = 1.125 × 437.5
= 492.19 grains
Answer: 1⅛ oz = 492.19 grains of shot.
Question 2: An arrow weighs 0.7 oz total. Express in grains for a spine chart.
Solution:
Weight in grains = 0.7 × 437.5
= 306.25 grains
Answer: 0.7 oz = 306.25 grains total arrow weight.
Question 3: Convert 3 oz of black powder to grains.
Solution:
Weight in grains = 3 × 437.5
= 1,312.5 grains
Answer: 3 oz = 1,312.5 grains of powder.
Practice Questions: Ounces to Grains
Try solving these on your own to test your understanding:
- Convert 0.5 oz to grains. (Answer: 218.75 grains)
- A bullet weighs 0.38 oz. How many grains? (Answer: 166.25 grains)
- Express 2 oz in grains. (Answer: 875 grains)
- An arrowhead weighs 0.23 oz. Convert to grains. (Answer: 100.625 grains)
- How many ounces is a 300-grain bullet? (Answer: 0.686 oz)
Archery: Total Arrow Weight in Grains
Archers measure total arrow weight (TAW) in grains because it determines kinetic energy and penetration. A typical hunting arrow weighs 350-500 grains total (shaft + point + fletching + nock). The minimum recommended weight for ethical hunting is 5 grains per pound of draw weight (e.g., 70 lb bow → minimum 350 grain arrow). Lighter arrows fly faster but penetrate less.
Shotgun Payloads in Ounces and Grains
Shotgun ammunition is labeled by payload weight in ounces: 7/8 oz (light target), 1 oz (standard target), 1⅛ oz (heavy target/field), 1¼ oz (hunting), and 1½ oz (turkey/magnum). Reloaders often need the grain equivalent to calculate charges per pellet count. A 1 oz payload of #7.5 shot contains roughly 350 pellets at about 1.25 grains each.
Key Takeaways
- 1 ounce = 437.5 grains exactly.
- Derived from: 1 lb = 7,000 grains and 1 lb = 16 oz.
- Used in ammunition reloading, archery, and precision weighing.
- Shotgun payloads are listed in ounces on the box (convert to grains for reloading).
- Arrow weight is measured in grains for ballistic calculations.
- The grain is identical across avoirdupois, troy, and apothecary systems.
Ounce to Grain Conversion Formula
grain = ounce × 437.5000000
1 ounce = 437.5000000 grain
1 grain = 0.0022857 ounce
Reverse: ounce = grain × 0.0022857
Frequently Asked Questions
How many grain are in 1 ounce?
There are 437.5000000 grain in 1 ounce. To convert ounce to grain, multiply the value by 437.5000000.
How do I convert ounce to grain?
Multiply your ounce value by 437.5000000 to get the equivalent in grain. For example, 5 ounce = 5 × 437.5000000 = 2187.50000 grain.
How do I convert grain to ounce?
Multiply your grain value by 0.0022857 to get the equivalent in ounce. Alternatively, divide by 437.5000000.
What is 10 ounce in grain?
10 ounce is equal to 4375.00000 grain.
What is 100 ounce in grain?
100 ounce is equal to 43750.00000 grain.