Weight Conversions

Continuing with yesterday’s cooking essentials themes, I was reading one of those random facts pages on Facebook and it said that 2 of the top 10 most Googled questions are about converting ounces!

So Thought I’d help you out with a quick kitchen-based maths lesson. (Yay! ….Sorry if that sounded sarky, but my Yay was genuine, I’m a nerd and proud!)

**Most importantly: 1oz is 28g but most cookbooks and older conversion charts (like I had at school) use 25g because it makes the math easier and the graduations on mechanical scales are 25’s, so we’ll roll with that (unless you have OCD and fancy electronic scales, in which case use 28g 😉 )**

Cooking weights:

  • 1oz = 25g (BTW old measures are imperial and modern are metric, if someone refers to them as such)
  • To convert oz to g, multiply (x) by 25, from g to oz divide by 25 (100g/25 = 4oz)


Liquid measures:

  • 1floz (fluid ounce) = 25ml (same as above, 28 but rounded for simplicity)
  • 1pint= 568ml, (you will probably NEVER use this as every jug I’ve ever used has both metric and imperial, if you have a 25ml increment jug, then aim for half-way between 550 and 575 ml)
  • …..but 1/2 pint is quite often rounded to 300ml ?!


Cups and spoons:

  • 1tsp (teaspoon) is about 5ml or 7.5g dry ingredients (g usually = ml but spoons are tricky because you can heap dry ingredients)
  • 1 dessert spoon 10ml
  • 1 tbsp (tablespoon) is 15ml
  • a ‘pinch of’ seasoning should always be less than 1/2 tsp


  • 1 Cup = 250ml or about 8oz (it’s trickier with dry ingredients as a cup of rice cereal will weigh less than a cup of compacted brown sugar, but 8oz about right for flour, regular sugar and fat)

Tip: If you have no cups, either use a measuring jug to the 250ml line or look at the ratio…if it’s one cup of each ingredient, whether you use 6oz or 8oz or 10 oz all ingredients the same (8oz of sugar, 8oz flour etc) or if there’s 2 cups of flour to 1 cup butter then make sure the flour is twice weight of the butter (12oz flour, 6oz butter for example).


Bigger measures: (Probably won’t need these in the kitchen, but useful to know)

  • 16oz in 1lb (pound)
  • 14lb in 1 Stone
  • 1000g in 1kg
  • 1kg = 2.2lbs (so to convert same as oz to g: kg to lbs multiply by 2.2, lbs to kg divide by 2.2
  • 1lb approx. 450g



I hope that helps and isn’t too much math on a Tuesday morning, but hopefully now you can use the tools and recipes (and perhaps a calculator) you’ve got more confidently.

Happy baking! x


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s