Convert Ounces to Grams Instantly
Use this Ounces to Grams converter for fast everyday weight and mass conversions. One standard avoirdupois ounce equals exactly 28.349523125 grams. Enter any whole or decimal ounce value to get grams instantly, then view kilograms, pounds and other useful mass units.
Convert ounces to grams, reverse grams to ounces, combine pounds and ounces into grams, or convert one mass value across several common units.
Enter any standard ounce value to calculate grams and related mass units instantly.
Decimals such as 0.25, 1.5 and 12.75 are supported.
For the standard avoirdupois ounce.
Reverse the calculation by dividing grams by 28.349523125.
Combine pounds and ounces, then convert the total weight into grams and kilograms.
Convert a starting mass across grams, kilograms, ounces, pounds, metric tons and US short tons.
This calculator uses the standard avoirdupois ounce used for general weight measurement in the United States and many everyday applications. A troy ounce is a different unit and should not be substituted.
One avoirdupois ounce is exactly 28.349523125 grams.
Convert grams back to ounces by dividing by the same factor.
Common ounce values are listed in a mobile-scrollable table.
Calculator cards, tables, figures and FAQs adapt to small screens.
To convert ounces to grams, multiply the number of ounces by 28.349523125. The ounce used here is the standard avoirdupois ounce, the unit normally meant when recipes, packaged goods, postal weights and general household measurements say “oz.” Because the relationship between the international pound and the kilogram is exact, the avoirdupois ounce-to-gram factor is exact as well.
Example: 5 oz × 28.349523125 = 141.747615625 g.
For everyday use, it is usually reasonable to round the result to one or two decimal places unless your work requires more precision. For example, 5 oz is commonly written as 141.75 g. In technical calculations, laboratory work or carefully controlled product specifications, keep more decimal places until the final reporting step.
The international avoirdupois pound is exactly 0.45359237 kilograms. One pound contains exactly 16 avoirdupois ounces. Dividing 453.59237 grams by 16 gives exactly 28.349523125 grams per ounce. This makes the conversion stable and reproducible.
Use a whole number or decimal ounce value.
Take 28.349523125 grams for each ounce.
Multiply ounces by the exact factor.
Choose precision appropriate to your task.
Report the answer clearly in grams (g).
For authoritative unit-conversion guidance, see the NIST Guide to SI conversion factors. For background on SI units and the kilogram, the BIPM SI Brochure is the international reference.
The following table gives common ounce-to-gram values. On mobile devices, swipe horizontally inside the table wrapper to view all columns.
| Ounces (oz) | Grams (g) | Kilograms (kg) | Pounds (lb) |
|---|---|---|---|
| 0.25 oz | 7.087380781 g | 0.007087381 kg | 0.015625 lb |
| 0.5 oz | 14.174761563 g | 0.014174762 kg | 0.03125 lb |
| 1 oz | 28.349523125 g | 0.028349523 kg | 0.0625 lb |
| 2 oz | 56.69904625 g | 0.056699046 kg | 0.125 lb |
| 4 oz | 113.3980925 g | 0.113398093 kg | 0.25 lb |
| 8 oz | 226.796185 g | 0.226796185 kg | 0.5 lb |
| 12 oz | 340.1942775 g | 0.340194278 kg | 0.75 lb |
| 16 oz | 453.59237 g | 0.45359237 kg | 1 lb |
| 24 oz | 680.388555 g | 0.680388555 kg | 1.5 lb |
| 32 oz | 907.18474 g | 0.90718474 kg | 2 lb |
These rounded values are convenient for mental estimates. Use the calculator above when you need more decimal precision.
Multiply 3 by 28.349523125. The result is 85.048569375 grams, or about 85.05 g when rounded to two decimals.
6.5 × 28.349523125 = 184.2719003125 grams. This is approximately 184.27 g.
12 × 28.349523125 = 340.1942775 grams. Because 12 ounces is three-quarters of a pound, the answer also equals 0.3401942775 kg.
1.25 × 28.349523125 = 35.43690390625 grams. This example shows why a calculator is useful for fractional ounce values.
An ounces to grams calculator is useful whenever US customary weight notation needs to be compared with metric labeling. Cooking and baking are common examples: a recipe may list cheese, chocolate, butter, meat or dry ingredients in ounces while a kitchen scale displays grams. Converting the recipe first can make weighing easier and more repeatable.
Product packaging is another common case. US packaging may emphasize ounces while international packaging often uses grams or kilograms. Postal services, craft supplies, fitness equipment, hobby materials and small hardware items can also use different units depending on the seller or country.
For larger values, it can help to connect this page with other mass tools. You can move from grams to kilograms with our Grams to Kilograms converter, compare larger customary units with the Kilograms to Pounds converter, or use Tons to Kilograms and Metric Tons to Kilograms when the mass is much heavier.
The ounce on this page is the avoirdupois ounce. It belongs to the avoirdupois system used for general weight measurement. There are 16 avoirdupois ounces in one pound.
The gram is a metric mass unit equal to one-thousandth of a kilogram. It is widely used for food, medicine labeling, science, manufacturing and everyday metric measurements.
For the reverse calculation, divide grams by 28.349523125. The reverse formula is:
Example: 100 g ÷ 28.349523125 ≈ 3.527396195 oz.
If you often work in the reverse direction, use the second calculator panel above or visit the related Grams to Ounces converter.
The exact conversion factor contains many decimal places, but the correct displayed precision depends on the original measurement and the purpose of the result. A kitchen recipe usually does not benefit from showing nine decimal places, while a technical worksheet may need more precision.
A good practice is to keep full precision in intermediate calculations and round only the final reported number.
The same mass can be expressed as 1 oz or 28.349523125 g.
When a recipe is written in ounces but your scale is set to grams, convert each ingredient individually instead of converting the total recipe weight. Different ingredients may also be listed by volume, so make sure you are converting weight ounces, not fluid ounces. For packaged products, the ounce and gram values printed on the label may be rounded according to labeling rules, so a calculator can sometimes produce a slightly different last digit from the package.
For shopping or product comparison, grams are particularly useful because metric package sizes are easy to compare using base-10 relationships. A 500 g package is 0.5 kg, while an 8 oz package is approximately 226.8 g. When comparing prices, first convert both products to the same unit and then compare cost per gram or cost per ounce.
The ounce-to-gram relationship is also useful in fitness and nutrition contexts when food portions are described in ounces but nutrient data is given per 100 grams. Converting the serving mass to grams helps you scale the nutrition numbers consistently.
Quick answers about oz to g formulas, common values, rounding and ounce types.