1 oz = 28.3495 g
Roughly a single serving. Multiply 1 oz by 28.349523125. The result is 28.3495 g.
Fast answers, clean math
Ounces to grams converter
Enter ounces and get grams instantly. This page also shows the formula so you can sanity-check the result.
Unit converter
Convert ounces to grams
Advertisement
Formula
How to convert ounce to gram (oz → g)
One ounce equals exactly 28.349523125 grams. This is an exact definition, not an approximation, so the factor never changes.
Formula: grams = ounces × 28.349523125
To go the other way, multiply by 0.0352739619: ounces = grams × 0.0352739619.
For example, 1 oz × 28.349523125 = 28.3495 g.
| Ounce (oz) | Gram (g) |
|---|---|
| 1 oz | 28.3495 g |
| 2 oz | 56.699 g |
| 3 oz | 85.0486 g |
| 4 oz | 113.3981 g |
| 6 oz | 170.0971 g |
| 8 oz | 226.7962 g |
| 10 oz | 283.4952 g |
| 12 oz | 340.1943 g |
| 16 oz | 453.5924 g |
| 32 oz | 907.1847 g |
Step by step
Worked ounce to gram examples
8 oz = 226.7962 g
Roughly half a pound. Multiply 8 oz by 28.349523125. The result is 226.7962 g.
16 oz = 453.5924 g
Roughly a full pound. Multiply 16 oz by 28.349523125. The result is 453.5924 g.
Background
What is a ounce?
An ounce (avoirdupois) is a unit of mass equal to exactly 28.349523125 grams, or one sixteenth of a pound.
The ounce also derives from the Roman system, where an uncia was one twelfth of a unit. The avoirdupois ounce used for everyday weight became standard in the English-speaking world.
Everyday scale: An ounce is about the weight of a slice of bread or a AA battery. A standard letter mailed in the US is often priced by the ounce.
System: imperial / US customary.
Background
What is a gram?
A gram is a metric unit of mass equal to one thousandth of a kilogram.
The gram was originally defined in 1795 as the mass of one cubic centimeter of water at the temperature of melting ice, making it a convenient everyday unit.
Everyday scale: A gram is about the mass of a small paperclip or a US dollar bill. A teaspoon of sugar is roughly 4 grams.
System: metric (SI).
Where it helps
When you need to convert ounce to gram
Travel and shipping
Airlines, postal services, and couriers set weight limits in kilograms or pounds depending on the region. Converting before you pack or ship avoids overweight fees and rejected parcels.
Cooking and baking
Recipes from different countries list ingredients in grams or ounces. Converting accurately matters most in baking, where ratios of flour, sugar, and butter change the result.
Health and fitness
Body weight, dosages, and nutrition labels mix metric and imperial units. Converting keeps tracking consistent whether your scale, app, or doctor uses kilograms or pounds.
Accuracy
Precision and common mistakes
The ounce to gram factor is exact by definition, so any error comes from rounding too early. Keep full precision through your calculation and round only the final answer to the precision your task needs.
A common mistake is rounding the conversion factor to two or three digits before multiplying, which can shift the result noticeably on large values. Multiply first, then round. Always keep the unit label with the number so the meaning is never lost.
| Use case | Good rounding |
|---|---|
| Body weight and luggage | 1 decimal place |
| Recipe ingredients | Whole grams or quarter ounces |
| Shipping and postage | Round up to the next billing step |
| Lab and pharmacy work | Use the exact factor, then round at the end |
Plain answers
Ounce to gram FAQ
How do you convert ounce to gram?
Multiply the number of ounces by 28.349523125. That single factor converts any ounce value to grams.
How many grams are in one ounce?
One ounce equals 28.349523125 grams.
What is 8 oz in g?
8 ounces equals about 226.7962 grams.
Is the ounce to gram conversion exact?
Yes. The factor is fixed by international definition, so ounce to gram is an exact conversion rather than an estimate.
How can I estimate ounce to gram in my head?
Multiply ounces by 28, so 4 ounces is about 112 g.