What is a grams to ounces converter?
A grams to ounces converter is an online tool that changes a mass expressed in grams (g), a metric unit, into ounces (oz), a unit from the imperial and US customary systems. It also works in reverse, turning ounces back into grams, so you can move between the two systems in either direction without doing the arithmetic by hand.
Grams are the everyday metric unit for small masses. They appear on food packaging, in recipes, in postal rates and in laboratory work almost everywhere in the world. Ounces, by contrast, remain common in the United States and, to a lesser extent, in the United Kingdom, particularly for food portions, cooking and the weight of letters and small parcels. Because both units describe the same quantity — mass — you can always express a value in one using the other.
How does it work?
The conversion rests on a single fixed relationship: one ounce (the avoirdupois ounce used for everyday weights) equals exactly 28.349523125 grams. To turn grams into ounces you divide by this number, and to turn ounces into grams you multiply by it.
Because the factor is defined exactly, the conversion introduces no error of its own; any rounding you see comes only from how many decimal places you choose to display.
Formula
To convert grams to ounces, divide the mass in grams by 28.349523125:
To convert ounces to grams, multiply by the same factor:
Example conversions
Convert 100 grams to ounces
So 100 grams is about 3.5274 ounces — a little over three and a half ounces.
Convert 1 ounce to grams
One ounce is therefore approximately 28.35 grams.
Conversion table
| Grams (g) | Ounces (oz) |
|---|---|
| 1 | 0.0353 |
| 10 | 0.3527 |
| 50 | 1.7637 |
| 100 | 3.5274 |
| 250 | 8.8185 |
| 500 | 17.637 |
| 1000 | 35.274 |
Notes
- The ounce here is the avoirdupois ounce, the standard for food and general weight. The troy ounce used for precious metals is different (about 31.10 g), so do not use this converter for gold or silver quoted in troy ounces.
- For quick mental estimates, remember that 1 ounce is roughly 28 grams, and 100 grams is a little over 3.5 ounces.
- Sixteen ounces make one pound. If you are working with larger masses you may find our kilograms to pounds converter more convenient.
Frequently asked questions
How many grams are in an ounce?
There are exactly 28.349523125 grams in one avoirdupois ounce, usually rounded to 28.35 g for practical use.
How do I convert grams to ounces quickly?
Divide the number of grams by about 28.35. For a rough figure, dividing by 28 gets you close enough for everyday cooking.
Is a gram bigger than an ounce?
No. A gram is much smaller than an ounce; it takes just over 28 grams to make a single ounce.
Why is the conversion factor so precise?
The avoirdupois ounce is legally defined in terms of the kilogram, which fixes it at exactly 28.349523125 grams. That is why the factor can be stated to many decimal places without approximation.