Calculator
What the Ounce to Gram does
Ounce to Gram: 1 oz = 28.34952313 g, so multiply a ounce value by 28.34952313 to get gram, or divide to go back. Example: 1 oz = 28.34952313 g.
Result, How it was calculated and Reverse conversion, derived from Value, From and To. The result recalculates on every keystroke without a button press or a page reload.
It is mostly used by anyone working across two measurement systems. Having the exact factor matters more than a rough mental estimate.
Everything happens inside this page. Nothing you type is sent to a server, and there is nothing for us to store.
If you want to check the arithmetic, the field table, the method and a worked example are further down.
What do the Ounce to Gram fields mean?
The Ounce to Gram uses 3 inputs. The defaults are there to be replaced. They exist so the tool is never showing an empty result.
| Field | What to enter | Default |
|---|---|---|
| Value | required | 1 |
| From | choose from Microgram (µg), Milligram (mg), Gram (g), Kilogram (kg), Tonne (metric ton) (t) or Grain (gr) | Ounce (oz) |
| To | choose from Microgram (µg), Milligram (mg), Gram (g), Kilogram (kg), Tonne (metric ton) (t) or Grain (gr) | Gram (g) |
How does the Ounce to Gram work?
Both units are converted through mass's base unit (kg), so any of the 13 units in the dropdowns can be paired in either direction without loss of accuracy.
Factors follow the internationally agreed definitions. The inch has been exactly 25.4 mm since 1959, and an exact definition is used wherever one exists. Where a unit is fixed by measurement rather than by agreement, the accepted CODATA or IAU value is used.
Worked example
These are the values the Ounce to Gram loads by default, and the result it produces from them. These are the tool’s own default values and the result they produce, not an invented illustration.
| Value | 1 |
|---|---|
| From | Ounce (oz) |
| To | Gram (g) |
| Result | 28.34952313 g |
|---|---|
| How it was calculated | 1 oz = 28.34952313 g, so 1 × 28.34952313 = 28.34952313 g |
| Reverse conversion | 0.035273962 oz (if you meant 1 g) |
Ounces and grams
1 (avoirdupois) ounce equals exactly 28.349523125 grams: the everyday ounce used for food, body weight and general retail, as distinct from the heavier troy ounce used for precious metals.
Worth knowing
- A fast mental estimate is ounces × 28, which understates the true value by about 1.2%, usually fine for a recipe, but worth avoiding for anything requiring a precise gram figure.
- US recipes and product packaging routinely use ounces where the rest of the world uses grams (a "12 oz can" of soda, for instance, is 340 g/mL), making this one of the more frequently needed everyday conversions.
- If the value in question is gold, silver, platinum or a gemstone, confirm whether "ounce" means the avoirdupois ounce (28.35 g) or the troy ounce (31.10 g) before converting. Precious-metals markets exclusively use the troy ounce.
Definitions: BIPM SI Brochure · NIST reference on units
How to use it
- Fill in Value.
- Pick a value for From: the options are Microgram (µg), Milligram (mg), Gram (g), Kilogram (kg), Tonne (metric ton) (t) or Grain (gr).
- Pick a value for To: the options are Microgram (µg), Milligram (mg), Gram (g), Kilogram (kg), Tonne (metric ton) (t) or Grain (gr).
- Type a value and the answer is already there by the time you stop.
- The panel reports Result, How it was calculated and Reverse conversion.
- Both Copy Link and Print capture the current state, so pick whichever suits how you file things.
What this tool does not do
- Repeated conversions compound rounding, so convert once from the original value where possible.
- Factors use the internationally agreed definitions; some industries round them differently.
- The method is fixed. There is no option to substitute your own formula.
- The tool cannot tell whether a number was entered in the unit you intended, so double-check the labels.
Frequently asked questions
The form asks for Value, From and To. A starting value is in place for each, letting you treat it as a what-if tool rather than a data-entry form.
With the values loaded when the page opens, result comes out as 28.34952313 g. It recalculates the moment an input changes, which makes comparing scenarios quick.
Nothing is stored. The page has no back end to send data to, and holds your input only in memory.
It costs nothing, and there is no limit on repeat use.
Full double precision is used throughout; only the displayed figure is shortened.