How Many Grams Are in an Ounce and Ounces in a Gram?

Feel free to convert grams to ounces and ounces to grams using our conversion table and conversion calculators and learn the relationship between these two units.

Conversion of grams to ounces and ounces to grams is an easy one because both grams and ounces are units of mass, with a fixed ratio between these two units.

Grams to Ounces and Ounces to Grams Conversion Calculators

In order to convert grams to ounces and ounces to grams, feel free to use this conversion calculator - write the value that You have and click 'Calculate':

Conversion Formulas

Gram is a metric system unit of mass and it was first defined as a mass of 1 milliliter (1 cm³) of water at 0°C (later at 4°C) - modern definition of a gram and a kilogram is based on the fixed numerical value of the Planck constant h, but the actual difference is very small and can be ignored in everyday situations.

Thus, ounces-grams conversion formulas are:

1 ounce = 28.349523125 grams

1 gram = 0.03527396149 ounces

As one can see, 1 ounce is ~28.3495 grams or ~28.4 grams, which is accurate enough in most situations and it is very easy to remember - at least much easier than 28.3495 grams :)

Since this is the conversion of the two mass units, the actual conversion is very simple.

Conversion Examples

If You have 1734 grams, that would be:

1734 grams = 1734 * 0.035274 = ~61.165 ounces

Similarly, if You have 5.34 ounces, that would be:

5.34 ounces = 5.34 * 28.3495 = ~151.386 grams 

A Brief History of Ounces (Oz)

The ounce, a unit of weight used in various systems including the avoirdupois, troy, and apothecaries' systems, has a rich and varied history. Its usage and significance have evolved over centuries, spanning different cultures and measurement systems.

The relationship between ounces and grams, a more modern and standardized unit of measurement, highlights the evolution of weight measurement through history.

Origins of the Ounce

The word "ounce" is derived from the Latin word "uncia," which was a unit of measurement in ancient Roman times. An uncia was one-twelfth of the Roman pound, or "libra," which is where the abbreviation "lb" for the pound originates. The ounce began as a way to divide a pound into smaller portions, a practice that continued into medieval times and beyond.

Standardization and the Avoirdupois System

The ounce became more standardized with the advent of the avoirdupois system, which originated in France in the 14th century and was later adopted by the English. In the avoirdupois system, one pound is equal to 16 ounces. This system was primarily used for general goods and is still in use today in many countries, including the United States.

The Troy and Apothecaries' Ounces

Alongside the avoirdupois ounce, there are other types of ounces like the troy and the apothecaries' ounce. The troy ounce, used in the troy weight system, is primarily known for its use in weighing precious metals.

The apothecaries' system, which was used by pharmacists, also had its own version of the ounce. These systems had different definitions and uses, reflecting the varied needs for weight measurement in different trades.

Ounces and Grams

With the international adoption of the metric system, the gram became the standard unit of mass. One gram is defined as one-thousandth of a kilogram, the SI base unit of mass.

The relationship between ounces and grams is a key aspect of converting measurements between the metric system and systems that use ounces.

Grams to Ounces and Ounces to Grams Conversion Tables

Here are some grams to ounces and ounces to grams quick conversion charts to aid You with unit' conversions: