To convert ounces to grams, multiply by 28.349523125 (about 28.35). 1 oz is 28.35 g, 4 oz is 113.4 g, and 16 oz (1 lb) is 453.59 g.
US food packaging, deli counters and older recipes use ounces. Metric recipes and kitchen scales use grams, and weighing in grams is the most reliable way to bake.
How to use the ounces to grams converter
- Type the value in ounces into the box. Decimals are fine.
- The result in grams updates as you type, along with the working.
- Need the other way? Switch the direction menu, or open the grams to ounces converter.
Formula
An avoirdupois ounce is 1/16 of a pound: 0.45359237 kg ÷ 16 = 28.349523125 g exactly. This is the weight ounce, not the fluid ounce (a volume) or the troy ounce (31.1035 g) used for precious metals.
Worked example
A recipe calls for an 8 oz package of cream cheese. How many grams is that?
- 8 × 28.349523125 = 226.796.
- Result: 226.8 g. Packages are often labeled 226 g or 227 g.
Ounces to grams chart
Common values, rounded to 2 decimal places.
| Ounces (oz) | Grams (g) |
|---|---|
| 0.25 oz | 7.09 g |
| 0.5 oz | 14.17 g |
| 1 oz | 28.35 g |
| 2 oz | 56.7 g |
| 3 oz | 85.05 g |
| 4 oz | 113.4 g |
| 5 oz | 141.75 g |
| 6 oz | 170.1 g |
| 8 oz | 226.8 g |
| 10 oz | 283.5 g |
| 12 oz | 340.19 g |
| 14 oz | 396.89 g |
| 16 oz | 453.59 g |
| 20 oz | 566.99 g |
| 24 oz | 680.39 g |
| 32 oz | 907.18 g |
| 48 oz | 1,360.78 g |
| 64 oz | 1,814.37 g |
Weight ounces vs fluid ounces
"Ounce" on a bag of flour is a weight; "fl oz" on a bottle is a volume. They only match for water-like liquids: 1 fl oz of water weighs about 1.04 oz. For volume, see ounces to ml converter (fl oz to ml).
- Postage: US First-Class letter rates step by the ounce.
- Meat and cheese: a quarter-pound burger is 4 oz (113 g) before cooking.
- Gold and silver: prices are per troy ounce, 31.1035 g, which is about 10% heavier.
Quick mental math
Multiply by 30, then take off about 5%. 6 oz × 30 = 180, minus 9 = 171 g (exact: 170.1). Or use 28: 6 × 28 = 168.
Related conversions
Going the other way: grams to ounces converter. Related pages: lbs to kg converter, kg to lbs converter, stone to lbs converter. For other units in the same family, use the full weight converter or the cooking measurement converter.
Caveats and assumptions
- These are weight ounces. For fluid ounces (volume), use ounces to ml converter (fl oz to ml).
- Results show up to 10 significant digits; the chart is rounded for reading. Keep full precision for engineering, medical or legal work.
Frequently asked questions
How many grams are in an ounce?
28.349523125 g exactly, usually rounded to 28.35 g (nutrition labels round to 28 g).
How many grams is 4 oz?
113.4 g.
How many grams in a troy ounce?
31.1034768 g. Troy ounces are used only for precious metals.
Is an ounce of flour the same as an ounce of water?
By weight, yes: an ounce is an ounce. By volume, no: a cup of flour weighs about 4.25 oz while a cup of water weighs about 8.3 oz.
Sources
- NIST — SI Units: Mass — kilogram and the exact avoirdupois pound
- NIST SP 811 Appendix B.9 — Conversion factors — ounce (avoirdupois) and troy ounce to gram
- NIST Metric Kitchen — Cooking Measurement Equivalencies — household cup, spoon and fluid-ounce equivalents
This calculator gives estimates for planning and education. Check measurements, local codes, supplier specs and your school's official policy before relying on a result. See our disclaimer and how we build and check calculators.