Grain to Ounce Conversion Calculator: Free Online Tool

Convert grains to ounces with our free online weight converter.

Grain to Ounce Calculator

Grain
Ounce

How to Use the Calculator:

  1. Enter the value you want to convert in the 'From' field (Grain).
  2. The converted value in Ounce will appear automatically in the 'To' field.
  3. Use the dropdown menus to select different units within the Weight category.
  4. Click the swap button (⇌) to reverse the conversion direction.

How to Convert Grain to Ounce

Converting Grain to Ounce involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Grain = 0.00228571 ounces

Example Calculation:

Convert 5 grains: 5 × 0.00228571 = 0.0114285 ounces

Disclaimer: For Reference Only

These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.

Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.

What is a Grain and a Ounce?

The grain (gr) is a unit of mass in the traditional English weight systems (Avoirdupois, Troy, and Apothecaries'). It was originally based on the weight of a single grain of barley. It is defined as exactly 64.79891 milligrams (or 1/7000 of an avoirdupois pound).

The ounce (oz) is a unit of mass used in the British imperial and United States customary systems of measurement. The most common type today is the international avoirdupois ounce, defined as exactly 1/16 of an avoirdupois pound, or approximately 28.35 grams.

Note: The Grain is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Ounce belongs to the imperial/US customary system.

History of the Grain and Ounce

The grain is one of the oldest units of mass, dating back to antiquity, using seeds (like barley or wheat) as weight standards. It formed the legal basis for English weight systems and remains defined in terms of metric units today.

The term "ounce" derives from the Roman "uncia", which was one-twelfth of the Roman pound. Its value varied throughout history and regions. The avoirdupois ounce became standardized in the English-speaking world for general trade.

Common Uses for grains and ounces

Explore the typical applications for both Grain (imperial/US) and Ounce (imperial/US) to understand their common contexts.

Common Uses for grains

  • Ammunition: Measuring the mass of bullets and gunpowder charges.
  • Archery: Measuring the mass of arrows and arrowheads.
  • Medicine & Pharmacy: Historically used in the apothecaries' system; sometimes still used for measuring dosage of certain older medications (e.g., aspirin).
  • Jewelry: Used in the troy system (24 grains = 1 pennyweight).
  • Reloading: Handloading ammunition requires precise measurement in grains.

Common Uses for ounces

  • Cooking & Recipes: Standard unit in the US for measuring food ingredients like flour, sugar, spices, and non-liquid items in recipes.
  • Packaged Foods: Used for labeling the net weight of many packaged food products (e.g., cereal boxes, canned goods, snacks).
  • Postal Services: Used for determining the weight and cost of letters and small parcels, especially in the US.
  • Deli & Groceries: Common unit for measuring small portions of items like cheese, deli meats, and specialty foods.
  • Precious Metals: Often used to measure the weight of gold, silver, and other precious metals in jewelry and bullion.

Frequently Asked Questions

Questions About Grain (gr)

How many grains are in an ounce (avoirdupois)?

There are 437.5 grains (gr) in 1 avoirdupois ounce (oz).

How many grains are in a pound (avoirdupois)?

There are 7,000 grains (gr) in 1 avoirdupois pound (lb).

How many milligrams are in a grain?

There are exactly 64.79891 milligrams (mg) in 1 grain (gr).

About Ounce (oz)

How many ounces are in a pound?

There are 16 avoirdupois ounces (oz) in 1 pound (lb).

Is an ounce the same as a fluid ounce?

No. The ounce (oz) measures mass/weight, while the fluid ounce (fl oz) measures volume.

Where is the ounce commonly used?

It is primarily used in the United States for everyday measurements, and to some extent in the UK and Canada, though metric units are more prevalent globally.

Conversion Table: Grain to Ounce

Grain (gr)Ounce (oz)
10.002
50.011
100.023
250.057
500.114
1000.229
5001.143
1,0002.286

All Weight Conversions

Kilogram to GramKilogram to MilligramKilogram to PoundKilogram to OunceKilogram to StoneKilogram to Ton (metric)Kilogram to Ton (US)Kilogram to Ton (UK)Kilogram to MicrogramKilogram to CaratKilogram to SlugKilogram to Troy OunceKilogram to PennyweightKilogram to GrainKilogram to DramKilogram to QuintalKilogram to Atomic Mass UnitKilogram to Pavan (India)Kilogram to Kati (India)Kilogram to Masha (India)Kilogram to Dina (India)Kilogram to Pras (India)Kilogram to Lota (India)Gram to KilogramGram to MilligramGram to PoundGram to OunceGram to StoneGram to Ton (metric)Gram to Ton (US)Gram to Ton (UK)Gram to MicrogramGram to CaratGram to SlugGram to Troy OunceGram to PennyweightGram to GrainGram to DramGram to QuintalGram to Atomic Mass UnitGram to Pavan (India)Gram to Kati (India)Gram to Masha (India)Gram to Dina (India)Gram to Pras (India)Gram to Lota (India)Milligram to KilogramMilligram to GramMilligram to PoundMilligram to OunceMilligram to StoneMilligram to Ton (metric)Milligram to Ton (US)Milligram to Ton (UK)Milligram to MicrogramMilligram to CaratMilligram to SlugMilligram to Troy OunceMilligram to PennyweightMilligram to GrainMilligram to DramMilligram to QuintalMilligram to Atomic Mass UnitMilligram to Pavan (India)Milligram to Kati (India)Milligram to Masha (India)Milligram to Dina (India)Milligram to Pras (India)Milligram to Lota (India)Pound to KilogramPound to GramPound to MilligramPound to OuncePound to StonePound to Ton (metric)Pound to Ton (US)Pound to Ton (UK)Pound to MicrogramPound to CaratPound to SlugPound to Troy OuncePound to PennyweightPound to GrainPound to DramPound to QuintalPound to Atomic Mass UnitPound to Pavan (India)Pound to Kati (India)Pound to Masha (India)Pound to Dina (India)Pound to Pras (India)Pound to Lota (India)Ounce to KilogramOunce to GramOunce to MilligramOunce to PoundOunce to StoneOunce to Ton (metric)Ounce to Ton (US)Ounce to Ton (UK)Ounce to MicrogramOunce to CaratOunce to SlugOunce to Troy OunceOunce to PennyweightOunce to GrainOunce to DramOunce to QuintalOunce to Atomic Mass UnitOunce to Pavan (India)Ounce to Kati (India)Ounce to Masha (India)Ounce to Dina (India)Ounce to Pras (India)Ounce to Lota (India)Stone to KilogramStone to GramStone to MilligramStone to PoundStone to Ounce