Choose the right measurement system

Read the meaning of each unit

BatchLadle’s US customary system uses a cup of 236.5882365 mL. Its metric kitchen system uses a 250 mL cup, a 15 mL tablespoon, and a 5 mL teaspoon. These choices are stated definitions for the tool; a recipe can use another convention.

NIST also publishes approximate cooking equivalents using 240 mL for a cup. That practical approximation is distinct from the exact US customary definition. Do not combine the approximate cup with exact conversions without identifying the change.

Some publishers use a different spoon convention. Women’s Weekly Food specifies a 20 mL tablespoon. Keep that source spoon distinct from BatchLadle’s 15 mL metric tablespoon; a shared 250 mL cup does not make every smaller measure identical.

Respect source-specific measures

A source cup is the unit used by a cited ingredient reference when its physical volume is not established. It is not an extra national measurement system. You can scale the source’s own quantity while keeping that original basis visible.

If a reference defines the physical volume and matching preparation, the tool can use its weight-to-volume relationship for supported conversions. The result remains approximate because the ingredient reference is approximate.

Change the system deliberately

Inspect the selected source and ingredient state before switching US or metric. A system change must not quietly replace the source. If the chosen reference cannot support the requested conversion, use the explanation beside the result to decide what to change.

For a recipe already written in grams, leave the mass amounts in grams. Converting them into estimated cups and back adds uncertainty without helping the serving calculation.

Keep units in the output

Before saving or exporting, check that a cup quantity can be understood without the settings panel. Keep the selected system, source unit where relevant, and measurement notes with the recipe.

For international recipes, also check spoon definitions stated by the author. A label such as “metric” does not establish every regional convention. Use explicit millilitres when that is what the recipe provides.