# 100 grams sourdough starter to cups

Converts grams of sourdough starter to cups and back, from the weight of 1 cup (sourdough starter: 227 g).

- Page: https://www.acalculator.org/convert/100-grams-sourdough-starter-to-cups
- JSON spec: https://www.acalculator.org/convert/100-grams-sourdough-starter-to-cups.json
- Version: afdee78fa17c

## Default answer

Example with the default inputs (Grams (g) 100, Ingredient Sourdough starter, 227 g per cup): 100 g = 0.440529 cups (Sourdough starter, 227 g per cup).

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| value | Grams (g) | The amount in grams to convert. |
| result | Cups (cup) | The same amount in cups. |
| ingredient | Ingredient | What you are measuring. A cup of flour weighs less than a cup of water. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| value | Grams (g) | The amount in grams to convert. |
| result | Cups (cup) | The amount in cups. |

## Method

cups = grams ÷ 227, where grams per cup depends on the ingredient (sourdough starter: 227 g)

## Assumptions

- Grams per cup are USDA FoodData Central (SR Legacy) portion weights for one level US cup (8 US fluid ounces): all-purpose flour 125 g (FDC 168894), granulated sugar 200 g (FDC 169655), brown sugar, packed 220 g (FDC 168833), powdered sugar, unsifted 120 g (FDC 169656), whole milk 244 g (FDC 171265), butter 227 g (FDC 173410), olive oil 216 g (FDC 171413), honey 339 g (FDC 169640), white rice, uncooked 185 g (FDC 169756).
- Sourdough starter is 227 g per level US cup (8 oz): the King Arthur Baking ingredient weight chart lists 1 cup of starter at 227 to 241 g, and this page uses the low end.
- Water is pure water: 0.999975 kg per liter at 4 °C and 0.998207 kg per liter at 20 °C, from the Tanaka et al. (2001) density formula.
- How you fill the cup changes the weight: packed, sifted, or scooped flour can differ by 20% or more.
- Exact on the typed decimals: at most 6 decimal places (6 significant digits below 0.0001), rounded half up; an answer of 1 billion or more shows at most 15 significant digits.

## Worked examples

1. value = 250, ingredient = flour gives result = 2. Source: USDA FoodData Central SR Legacy 168894: 1 cup = 125 g.
2. value = 100, ingredient = sugar gives result = 0.5. Source: USDA FoodData Central SR Legacy 169655: 1 cup = 200 g.
3. value = 100, ingredient = sourdough-starter gives result = 0.440529.

## FAQ

### What is 100 grams of sourdough starter in cups?

100 grams of sourdough starter is 0.440529 cups. The formula is cups = grams ÷ 227: this page uses 227 g per level US cup (sourdough starter, from the King Arthur Baking ingredient weight chart).

### How do I convert grams of sourdough starter to cups?

cups = grams ÷ 227, where grams per cup depends on the ingredient (sourdough starter: 227 g). For example, 250 grams of sourdough starter is 1.101322 cups.

### How much does a cup of sourdough starter weigh?

227 to 241 g (8 to 8 1/2 oz), in the King Arthur Baking ingredient weight chart, which does not state the hydration of the starter. This page uses 227 g, so 100 g of starter is 0.440529 cups; at 241 g a cup it is 0.414938 cups.

### How many cups is 100 grams of another ingredient?

It depends on the ingredient, because a weight does not fix the volume. 100 grams is about, in cups: all-purpose flour 0.8; granulated sugar 0.5; brown sugar, packed 0.4545; powdered sugar, unsifted 0.8333; water at 4 °C 0.4227; water at 20 °C 0.4234; whole milk 0.4098; butter 0.4405; olive oil 0.463; honey 0.295; white rice, uncooked 0.5405. Pick the ingredient in the converter for its exact answer.

## Sources

- King Arthur Baking, Ingredient weight chart: sourdough starter, 1 cup = 8 to 8 1/2 oz = 227 to 241 g, retrieved 2026-10-19. https://www.kingarthurbaking.com/learn/ingredient-weight-chart
- USDA FoodData Central, SR Legacy portion weights for 1 cup: FDC 168894 all-purpose flour 125 g; FDC 169655 granulated sugar 200 g; FDC 168833 brown sugar, packed 220 g; FDC 169656 powdered sugar, unsifted 120 g; FDC 171265 whole milk 244 g; FDC 173410 butter 227 g; FDC 171413 olive oil 216 g; FDC 169640 honey 339 g; FDC 169756 white rice, uncooked 185 g. https://fdc.nal.usda.gov/
- Tanaka, M. et al. (2001), Recommended table for the density of water between 0 °C and 40 °C based on recent experimental reports, Metrologia 38, 301–309: pure water 999.9749 kg/m³ at 4 °C and 998.2067 kg/m³ at 20 °C. https://doi.org/10.1088/0026-1394/38/4/3
- NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B.8: Factors for Units Listed Alphabetically (bold factors are exact), retrieved 2026-10-18. https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors/nist-guide-si-appendix-b8