1 Cup Flour in Grams – Precise Conversion Charts

Converting cups to grams for flour is one of the most common challenges in baking. A single cup of all-purpose flour can weigh anywhere from 110g to 140g depending on how it is measured, which means recipes relying on cup measurements can produce wildly inconsistent results. Understanding exactly what 1 cup of flour weighs in grams—and why that number varies—is essential for anyone who wants consistent, predictable baking outcomes.

The discrepancy between 120g and 125g that appears across different sources reflects real differences in measurement methodology. British sources tend to cite 125g for standard all-purpose flour, while American baking authorities often list 120g. The difference matters most when scaling recipes up or down, or when swapping between American and European recipes.

This guide provides precise, source-backed conversions for flour and other common baking ingredients, along with explanations for why weight variations occur and how to achieve accuracy in your kitchen.

How Many Grams in 1 Cup of Flour?

The standard measurement for 1 cup of unsifted all-purpose flour is 120 grams when using the spoon-and-level method. This is the figure most commonly cited by major baking authorities including King Arthur Baking and is based on a US cup of 240ml. However, values across sources range from 110g to 140g depending on flour type, brand, and whether the flour has been sifted.

The Overview Grid: Common Ingredient Conversions

Key Conversion Insights

• Flour weight varies significantly by packing method, ranging from 120g unsifted to 110g sifted per cup
• Always use the spoon-and-level method for consistency: spoon flour into the cup, then sweep off the excess with a straight edge
• A US cup equals exactly 240ml, which differs from the 284ml cup used historically in the UK
• Weighing ingredients on a kitchen scale eliminates the 20–30g variation that occurs with volume measurements
• Different flour types have different densities: bread flour can weigh 130g per cup versus 120g for all-purpose
• Humidity and compaction during shipping can affect flour weight even before you open the bag
• Converting between grams and cups: 120g flour equals approximately 1 cup; 125g equals about 1.04 cups or 1 cup plus 1 teaspoon

Flour Conversion Table: Full Cup to Fractions

1/2 Cup Flour in Grams and Other Common Fractions

Half a cup of flour equals 60 grams when measured using the spoon-and-level method. This conversion is one of the most frequently sought in baking, appearing in recipes that call for moderate amounts of flour for items like pancakes, quick breads, and thick batters.

Breaking Down Quarter Cups and Smaller Measurements

One-quarter cup of unsifted all-purpose flour weighs 30 grams. This measurement is common in recipes for muffins, biscuits, and small batches of cookies. The sifted equivalent drops to 27g, a difference that becomes more significant when multiplied across multiple quarters.

For measurements smaller than a quarter cup, tablespoons become the primary unit. One level tablespoon of flour weighs 8–9g, while two level tablespoons equal approximately 15g. These smaller measurements matter most when adjusting seasoning, adding leavening agents, or making small recipe modifications.

Conversions for Larger Fractions: 1 1/2 and 1 1/4 Cups

One and a half cups of unsifted all-purpose flour converts to 180 grams. This measurement frequently appears in bread recipes, cookie batches, and larger cake preparations. For 1¼ cups, the weight is 150g, bridging the gap between standard and larger batch requirements.

The fraction-to-gram conversions hold fairly consistently across sources, though some British references use 125g as a baseline for “soft” flours. When converting 1/2 cup using the 125g standard, you get 63g rather than 60g—a minor difference that can affect delicate recipes but is usually negligible in everyday baking.

1 Cup of Other Baking Ingredients in Grams

While flour is the most commonly converted ingredient, other baking staples have their own specific weight relationships that differ markedly from flour. Understanding these differences helps when adapting recipes or scaling ingredients proportionally.

Sugar: Granulated, Brown, and Caster Varieties

Granulated white or caster sugar consistently measures 200g per cup when spooned and leveled—significantly heavier than flour. This consistency across sources makes sugar one of the more predictable conversions in baking. Brown sugar, however, presents more variation: packed brown sugar ranges from 180g to 220g per cup depending on how firmly it is pressed into the measuring cup.

Butter, Milk, and Water Conversions

Butter presents a wider range than sugar, weighing 227–240g per cup depending on whether it is diced and loosely packed or more firmly compressed. The variation occurs because butter contains both fat and water, and its density shifts based on temperature and how it is measured. For most recipes, 227g per cup serves as a reliable baseline.

Milk and water are much more consistent, with milk at 240–245g per cup and water at exactly 240g. This near-equivalence reflects the fact that milk is mostly water, with the remaining solids contributing only marginally to overall density. Water’s exact 240g-per-cup figure stems from the metric definition where 1ml of water weighs 1g.

Why Flour Weights Vary: 120g vs 125g Explained

The 5-gram difference between 120g and 125g per cup represents approximately a 4% variation—small enough to seem insignificant but large enough to affect delicate baked goods. In a cake that requires 3 cups of flour, this difference translates to 15g, or roughly one tablespoon of flour. For cookies, that same 15g can change spread, texture, and browning.

The variance originates partly from historical differences between American and British measurement conventions. UK cups historically used 284ml rather than the US standard of 240ml, and British baking traditions developed around different flour densities. Modern recipe writers may reference either system, creating confusion for those following international recipes.

Beyond origin, the specific measurement technique makes the largest impact. Flour scooped directly from a bag can weigh 130–140g per cup due to compaction, while the spoon-and-level method consistently produces 120g. This is why baking experts universally recommend against scooping flour directly from the container.

Understanding Cup-to-Grams Conversions for Baking Accuracy

Volume measurements like cups have inherent limitations that weight measurements eliminate entirely. A cup represents a fixed volume—240ml in the US system—but that volume of flour can contain dramatically different masses depending on how the flour is settled, sifted, or compacted.

Grams provide an objective, reproducible measurement that does not depend on technique. When a recipe specifies 240g of flour, that amount remains constant regardless of whether the flour is sifted, packed, or loosely spooned. This objectivity makes weight-based recipes inherently more reliable than volume-based ones.

The minor difference between US and metric cup measurements—240ml versus 250ml—does not account for the weight variations seen across sources. The real issue lies in how flour settles, how aggressively it is measured, and the specific variety and brand of flour being used. Professional bakers prioritize weight measurements for this reason, and home bakers who invest in a kitchen scale typically see immediate improvements in recipe consistency.

Expert Sources and Measurements

“For most all-purpose flour, 120 grams per cup is a reliable standard when using the spoon-and-level method. King Arthur specifies 120g (4¼ oz) for their all-purpose flour, which provides consistent results in our test kitchen.”

— King Arthur Baking Ingredient Weight Chart

“Unsifted flour: 120g per cup. Sifted flour: 110g per cup. The difference of 10 grams reflects the aeration that occurs during sifting. Always check your recipe for specific preparation instructions.”

— Doves Farm Conversion Table

“Community consensus from bakers suggests 120–128g per cup for unsifted all-purpose flour, with the range reflecting variations in brand, humidity, and measurement technique. Fluff the flour before spooning to reduce compaction.”

— Home Baking Community

Next Steps for Precise Baking

Achieving consistent baking results requires moving beyond cup measurements to weight-based precision. A digital kitchen scale represents the single most valuable investment for serious bakers, allowing you to follow any recipe regardless of its origin or measurement conventions.

Test your flour brand to understand its specific density. Different brands of all-purpose flour can vary by 5–10g per cup, which compounds across larger recipes. Once you know your flour’s behavior, you can adjust measurements accordingly or calibrate recipes to your specific ingredients.

For further guidance on applying these conversions to real recipes, explore our resources on How to Make Sourdough Bread and Mary Berry Yorkshire Pudding, both of which demonstrate precise measurement techniques for specific baking projects.

Frequently Asked Questions