Ounces to Grams Converter for Baking
Classic British recipes — the ones in the cookbooks we have all inherited — are written in ounces. This converter turns any ounce weight into grams for your kitchen scales, and works backwards from grams to ounces and pounds when a modern recipe needs translating the other way.
The ounces to grams chart
The full imperial ladder, 1 to 16 ounces, with gram equivalents rounded the way classic recipe books print them. The quarter-pound steps (4, 8, 12 and 16 oz) are the ones baking uses most.
| Ounces | Grams | Also known as |
|---|---|---|
| 1 oz | 28 g | — |
| 2 oz | 57 g | — |
| 3 oz | 85 g | — |
| 4 oz | 113 g | ¼ lb |
| 5 oz | 142 g | — |
| 6 oz | 170 g | — |
| 7 oz | 198 g | — |
| 8 oz | 227 g | ½ lb |
| 9 oz | 255 g | — |
| 10 oz | 283 g | — |
| 11 oz | 312 g | — |
| 12 oz | 340 g | ¾ lb |
| 13 oz | 369 g | — |
| 14 oz | 397 g | — |
| 15 oz | 425 g | — |
| 16 oz | 454 g | 1 lb |
Going the other way, the gram weights bakers meet most often are: 50g = 1.8 oz · 100g = 3.5 oz · 150g = 5.3 oz · 200g = 7.1 oz · 250g = 8.8 oz · 300g = 10.6 oz · 400g = 14.1 oz · 500g = 17.6 oz · 750g = 26.5 oz · 1000g = 35.3 oz.
Weighing the old way, accurately
An ounce is an ounce whatever the ingredient — unlike cups, weights do not change with what is in the bowl. That is why imperial recipes were always more reliable than American volume measures, and why converting them to grams is straightforward arithmetic rather than guesswork.
One traditional trick is worth knowing: the classic sponge rule weighs the eggs first (in their shells) and matches the flour, butter and sugar to that weight. Four medium eggs weigh about 8 oz (225g), which is how the familiar "eight, eight, eight and four" sponge formula comes about. If your inherited recipe just says "the weight of the eggs in flour", you now know what to do.
Frequently asked questions
How many grams are in an ounce?
One ounce is exactly 28.3495 grams. In the kitchen everyone rounds it: 1 oz = 28g, and the classic quarter-pound steps are 4 oz = 113g, 8 oz = 227g and 16 oz (1 lb) = 454g.
How many ounces is 250 grams?
250g is 8.8 oz — a fraction over half a pound. The converter above gives the exact figure for any weight, including the pounds-and-ounces way older recipes write it.
Why do older British recipes use ounces?
Until metrication spread through publishing in the 1970s and 80s, British cookery was entirely imperial: ounces, pounds, pints and Gas Mark. Mary Berry’s earliest books were written that way, which is why a converter like this one still gets daily use.
Should I round ounces to the nearest gram or 5 grams?
For cakes, the nearest gram is ideal, but classic recipes were written expecting the nearest 5g — 4 oz was weighed as 115g in many books rather than 113g. The small difference rarely matters except in very precise patisserie.
How do I convert pounds to grams?
One pound is 16 ounces, which is 453.6g — call it 454g. Half a pound is 227g and a quarter pound is 113g. Enter any amount in pounds into the converter by multiplying by 16 first (2 lb = 32 oz).
Put it to work
Three classics that started life in ounces: