Gluten-Free Flour Weight Chart: Grams per Cup for 9 Major Brands (and Why the Spread Is Over 20%)

One cup of gluten-free flour blend weighs anywhere from 120 g to about 150 g depending on the brand. Using the wrong number throws off hydration, structure, and rise. Below is a weight chart with manufacturer-published grams per cup for the major blends, plus notes on what to do when a recipe doesn't specify a brand.

Prices checked September 2026 and vary by store.

Key takeaways

• A cup of King Arthur Measure for Measure weighs 120 g; a cup of Cup4Cup weighs 140 g; a cup of Bob's Red Mill 1-to-1 weighs 148 g by its label. That spread changes the texture of everything you bake.
• Always use the weight published by the brand whose flour you're using — not a generic "130 g per cup" number.
• Bob's Red Mill 1-to-1 and King Arthur Measure for Measure are the two most common blends in home gluten-free baking, and they differ by 28 g per cup.
• If a recipe lists only cups and doesn't name a flour brand, 130–135 g per cup is a reasonable starting point for most rice-based blends.
• A basic digital kitchen scale eliminates cup-measurement guesswork entirely and is the single most impactful tool upgrade for gluten-free baking.
• Starch-heavy blends (like Cup4Cup) and blends built on sweet rice flour (like Bob's 1-to-1) pack denser per cup than blends with cellulose and lighter grinds (like King Arthur).

Gluten-free flour weight chart: grams per cup by brand

This table uses the weight each manufacturer publishes on its packaging, website, or nutrition label. Where a brand publishes only a nutrition-label serving size (for example, 1/4 cup = 37 g), we multiply it out to a full cup and say so. All values are for the "spoon and level" method unless otherwise noted.

Notice the range: King Arthur and Pamela's at 120 g and Bob's Red Mill at 148 g sit 28 g apart. In a recipe calling for 3 cups of flour, that gap balloons to 84 g — enough to turn a moist cake into a dry one or make bread dough too slack to hold shape. If you struggle with dry, crumbly gluten-free bakes, measuring by weight instead of cups is often the fix.

Why gluten-free flour weights vary so much between brands

Wheat all-purpose flour lands at roughly 120–125 g per cup no matter who mills it, because the base grain and grind are nearly identical. Gluten-free blends use different ratios of rice flour, starches, and additives, so their bulk density changes brand to brand.

Three factors drive the gap:

• Starch and sweet-rice content. Cornstarch, potato starch, and glutinous (sweet) rice flour pack more densely than brown rice flour. Cup4Cup is cornstarch-forward and Bob's 1-to-1 leads with sweet white rice flour, which is part of why they weigh 140 g and 148 g per cup versus King Arthur's 120 g.
• Grind fineness and fillers. Finely milled rice flour settles differently than standard-grind rice flour, and King Arthur's blend includes cellulose, which is very light. Fine grinds also tend to produce a less gritty texture in the final bake.
• Added binders. Most blends include xanthan or guar gum, which slightly changes how the flour settles in a measuring cup.

How to use this chart when a recipe doesn't name a brand

Many gluten-free recipes online just say "gluten-free flour blend" without specifying which one. Here's what to do:

1. Check the recipe developer's site. Most serious GF bakers mention their preferred brand in an FAQ or about page. If the developer uses King Arthur, use 120 g per cup.
2. Default to 130–135 g per cup. This is the rough midpoint of the most popular blends and will get you within about 10 g of most brands.
3. Adjust by texture. If your dough or batter looks too thick, it probably is. Gluten-free batters should generally be slightly wetter than their wheat counterparts. Add liquid 1 tablespoon at a time.

If you're converting a wheat recipe to gluten-free, start by replacing all-purpose flour 1:1 by weight (not volume) with a blend that includes xanthan gum. Our all-purpose flour substitution page covers the ratios for single-flour swaps like brown rice flour or cassava flour.

King Arthur vs Bob's Red Mill vs Cup4Cup: the 3 most common blends compared

These three blends account for a large share of gluten-free baking in U.S. home kitchens. Here's how they stack up beyond just weight per cup.

The practical consequence of the weight gap: a recipe developed with Cup4Cup or Bob's at 140–148 g per cup will need a few tablespoons less liquid if you swap in King Arthur by volume, because a cup of King Arthur brings about 20–28 g less flour to the bowl. Weighing sidesteps the whole problem.

For a deeper side-by-side on Bob's and King Arthur, see our Bob's vs King Arthur gluten-free flour comparison.

Who should buy which

• King Arthur Measure for Measure: Best if you bake a lot of gluten-free bread and want a GFCO-certified, dairy-free blend. The lighter cup weight means recipes designed for it tend to have higher hydration, which helps with rise.
• Bob's Red Mill 1-to-1: Best all-rounder for cookies, muffins, and quick breads, and the only one of the three made in a dedicated gluten-free facility — though it carries no third-party seal. Sold in 22-oz and 44-oz bags.
• Cup4Cup: Best for pastry and pie crusts where a tender, flaky result matters more than chew. The high starch content mimics cake flour behavior. It is both GFCO-certified and made in a dedicated facility; the tradeoff is price.

Single-ingredient gluten-free flours: grams per cup

If you're building your own blend or following a recipe that calls for individual flours, these weights matter just as much. The figures below come from King Arthur Baking's published ingredient weight chart, except cassava flour, which uses Bob's Red Mill's label serving size.

Potato starch at 152 g per cup versus oat flour at 92 g per cup is a 65% difference. Swapping one for the other by volume without adjusting would wreck any recipe. This is exactly why a kitchen scale is non-negotiable for serious gluten-free baking.

Why a kitchen scale matters more in gluten-free baking than wheat baking

With wheat flour, a 10 g measurement error per cup is annoying but usually survivable — gluten is forgiving and stretches to accommodate slight hydration changes. Gluten-free doughs have no such safety net. Without the elastic protein network that gluten provides, every gram of flour directly affects how much liquid the starches absorb, how much the bake rises, and whether the center stays gummy or bakes through.

A decent digital kitchen scale is inexpensive and pays for itself quickly by eliminating failed batches. We recommend the OXO Good Grips 11lb Food Scale for its large platform (fits a mixing bowl easily) and 1 g resolution.

Measuring method matters as much as brand. The "dip and sweep" method packs roughly 10–15% more flour into a cup than "spoon and level," which is why manufacturers specify a method alongside their cup weight and why the same bag can give two bakers two different results.

GFCO vs FDA labeling: what the certification on your flour bag actually means

Two standards dominate gluten-free labeling in the U.S.:

• GFCO (Gluten-Free Certification Organization): Tests to under 10 ppm (parts per million) of gluten with regular audits. This is the stricter standard. King Arthur, Cup4Cup, Namaste, Better Batter, Pamela's, and gfJules all carry GFCO certification on the blends above.
• FDA "gluten-free" label: Requires under 20 ppm. Bob's Red Mill (which batch-tests in-house in a dedicated facility), Pillsbury, and Anthony's use this labeling without a GFCO mark on these blends.

Certification and facility are separate questions. King Arthur is GFCO-certified but states its certified products share equipment with wheat and other allergens; Bob's Red Mill is not certified but mixes and packages in a dedicated gluten-free facility; Cup4Cup, Namaste, and gfJules are both certified and made in dedicated facilities. If you're highly sensitive, look for both a third-party seal and a dedicated facility.

How to convert a wheat recipe to gluten-free flour by weight

The simplest approach:

1. Find the total flour weight in the wheat recipe (if it's in cups, use 120–125 g per cup for all-purpose wheat flour; King Arthur's chart uses 120 g).
2. Replace that weight 1:1 with your chosen gluten-free blend.
3. If your blend doesn't include xanthan gum, add 1 teaspoon per cup of flour for bread or 1/2 teaspoon per cup for cookies and cakes.
4. Expect to add 1–2 tablespoons more liquid than the original recipe calls for. Gluten-free blends often feel drier at first but hydrate as they rest.
5. Let the batter rest 15–20 minutes before baking. This gives the starches time to absorb liquid and reduces grittiness.

For bread specifically, gluten-free doughs behave more like thick batters than kneadable doughs. If you're making sandwich bread, see our gluten-free bread guide for store-bought options while you dial in a recipe.

Common weight chart mistakes that ruin gluten-free bakes

These come up constantly in gluten-free baking forums:

• Using a wheat flour weight for a GF blend. All-purpose wheat flour is about 120–125 g per cup. If you use that number for Bob's Red Mill 1-to-1 (148 g), you'll under-measure by 23–28 g per cup — 70–84 g in a 3-cup recipe. Your bake will be too wet.
• Confusing potato starch with potato flour. Potato starch is 152 g per cup. Potato flour is about 184 g per cup. They are completely different products with different absorption rates. Swapping them will produce an inedible result.
• Assuming all rice flour weighs the same. White rice flour (142 g per cup on King Arthur's chart) and brown rice flour (128 g) are not interchangeable by volume.
• Ignoring the measuring method. The "dip and sweep" method packs 10–15% more flour into a cup than "spoon and level." If the recipe developer scooped and you spooned, you're already off by 15 g or more per cup.

Frequently asked questions

How many grams is 1 cup of gluten-free flour?

It depends on the brand. King Arthur Measure for Measure is 120 g per cup, Cup4Cup is 140 g, and Bob's Red Mill 1-to-1 is 148 g by its label serving size. If a recipe doesn't specify a brand, 130–135 g is a reasonable default for most rice-starch blends. Always check the manufacturer's label or website for the exact number.

Can I substitute gluten-free flour blends 1-to-1 by volume?

Not reliably. A cup of King Arthur weighs 20 g less than a cup of Cup4Cup and 28 g less than a cup of Bob's 1-to-1. Over 3 cups, that's 60–84 g of difference — enough to change the texture significantly. If you must swap brands, measure by weight using the chart above rather than by cups.

Do I need to add xanthan gum to gluten-free flour blends?

Most popular blends — King Arthur, Bob's Red Mill 1-to-1, Cup4Cup, Better Batter, gfJules, and Pillsbury — already include xanthan gum, and Namaste and Pamela's include guar and/or xanthan gum. Check the ingredient list before adding more. Double-dosing xanthan gum makes baked goods gummy and rubbery. If your blend doesn't include it, add about 1 teaspoon per cup of flour for bread and 1/2 teaspoon for cakes.

Why does my gluten-free baking always turn out dry?

The most common cause is too much flour by volume. If you're scooping flour directly from the bag, you may be packing in 15% more than the recipe intends. Switch to weighing your flour with a digital scale. Other causes include overbaking (gluten-free goods continue to set as they cool, so pull them 2–3 minutes earlier than you think) and not enough fat or liquid. Our guide on fixing dry, crumbly gluten-free bakes covers all the common fixes.

Is there a gluten-free flour calculator I can use instead of a chart?

BakingSubs has a flour substitution calculator that lets you enter a flour type and amount, then converts it to grams or to an equivalent amount of a different flour. It handles both blends and single-ingredient flours. For quick lookups, bookmark the weight chart on this page and use it alongside the calculator for conversions between brands.