← Back to Blog

How Many Grams Is 1 Cup? Complete Conversion Guide

Published January 2026 • 4 min read • Nutrition

Quick Answer

1 cup = 125g to 240g depending on the ingredient. There's no single conversion because different ingredients have different densities. Water weighs 240g per cup, while flour weighs only 125g per cup.

If you're following a recipe from the US, you've probably seen measurements in "cups" instead of grams. In the UK, we use grams and millilitres, which are more accurate for cooking and nutrition tracking.

This guide shows you exactly how many grams are in 1 cup for common ingredients, so you can convert any American recipe to UK measurements.

Why Cup Measurements Vary by Ingredient

A cup is a volume measurement (how much space something takes up), while grams measure weight. Different ingredients have different densities:

This is why 1 cup of water = 240g but 1 cup of flour = 125g.

Complete Conversion Table: Cups to Grams

Liquids

Ingredient 1 Cup (g) 1/2 Cup (g) 1/4 Cup (g)
Water 240g 120g 60g
Milk 245g 123g 61g
Oil (vegetable/olive) 220g 110g 55g
Honey 340g 170g 85g

Flours & Grains

Ingredient 1 Cup (g) 1/2 Cup (g) 1/4 Cup (g)
Plain flour 125g 63g 31g
Self-raising flour 125g 63g 31g
Wholemeal flour 120g 60g 30g
Rolled oats 90g 45g 23g
Rice (uncooked) 185g 93g 46g

Sugars & Sweeteners

Ingredient 1 Cup (g) 1/2 Cup (g) 1/4 Cup (g)
Granulated sugar 200g 100g 50g
Caster sugar 200g 100g 50g
Brown sugar (packed) 220g 110g 55g
Icing sugar 120g 60g 30g

Fats & Dairy

Ingredient 1 Cup (g) 1/2 Cup (g) 1/4 Cup (g)
Butter 227g 113g 57g
Greek yogurt 245g 123g 61g
Cream cheese 225g 113g 56g
Grated cheese 100g 50g 25g

Nuts, Seeds & Other

Ingredient 1 Cup (g) 1/2 Cup (g) 1/4 Cup (g)
Almonds (whole) 140g 70g 35g
Walnuts (chopped) 120g 60g 30g
Peanut butter 250g 125g 63g
Cocoa powder 85g 43g 21g
Breadcrumbs 100g 50g 25g

How to Convert Cups to Grams

Follow these steps to convert any cup measurement:

  1. Identify the ingredient — Different foods have different conversions
  2. Find the conversion factor — Use the tables above
  3. Multiply if needed — For 2 cups, multiply the 1-cup value by 2

Example: A recipe calls for 1.5 cups of flour

UK Measurement Equivalents

In the UK, we typically use:

Quick conversions:

Why Grams Are More Accurate Than Cups

Professional bakers and nutritionists prefer grams because:

If you're tracking calories with an app like NutraSafe, weighing ingredients in grams gives you accurate nutrition data.

Tips for Accurate Measuring

If Using Cups (US Recipes)

If Using Grams (Recommended)

Common Questions

Is 1 cup always 240ml?

For liquids, yes — 1 US cup = 240ml. But the UK imperial cup is 284ml. Most modern recipes use US cups (240ml).

Why do different websites show different conversions?

Because it depends on how the ingredient is measured (sifted vs unsifted flour, packed vs loose brown sugar). Our values are based on standard measuring techniques.

Can I use a mug as a cup?

No — a standard US cup is exactly 240ml. Most mugs are 250-350ml, which will throw off your recipe. Use proper measuring cups or kitchen scales.

Do I need to sift flour before measuring?

Only if the recipe says "1 cup sifted flour." If it says "1 cup flour, sifted," measure first, then sift. For grams, it doesn't matter — 125g is 125g whether sifted or not.

Track Your Nutrition in Grams

If you're counting calories or tracking macros, measuring ingredients in grams makes nutrition tracking much easier. UK food labels show nutrition per 100g, so you can calculate exactly what you're eating.

Use a food scanner app like NutraSafe to:

Example: If you eat 50g of oats (½ cup), scan the barcode and enter "50g" to see exact calories and macros.

Final Thoughts

The answer to "how many grams is 1 cup" depends entirely on what you're measuring. Use the conversion tables above for accurate results, or better yet — invest in digital kitchen scales and measure everything in grams for perfect recipes every time.

Save this page for quick reference when converting American recipes to UK measurements!

← Back to Blog

Last updated: February 2026