Rice vinegar

One US cup of rice vinegar weighs 238.7 grams (8.4 ounces). Going the other way, 100 grams is about 0.42 cups.

Also called rice wine vinegar, unseasoned rice vinegar, natural rice vinegar, Japanese rice vinegar, komezu, plain rice vinegar.

Condiments and sauces compared: cup weights side by side, the source behind each, and why they differ.

A cup of unseasoned rice vinegar weighs about 238.7 g (8.4 oz), barely more than a cup of water (236.6 g). Kikkoman's foodservice gallon is the measured figure, and two general vinegar tables, one Australian and one Japanese, agree within 1%.

Rice vinegar is a mild vinegar brewed from rice, used across Japanese, Chinese and Korean cooking: in sushi rice, dressings, pickles, dipping sauces and stir-fries. It is gentler than white vinegar, at about 4 to 4.5% acidity against 5%. It is sometimes sold as rice wine vinegar; the two names mean the same product. Seasoned rice vinegar, sold for sushi rice, has sugar and salt added and is a different product, heavier than the plain vinegar this page covers.

The figure comes from Kikkoman. Its foodservice bulletin for 1-gallon rice vinegar, diluted with water to 4.2% acidity, gives a package net weight of 8.420 lb. That is 3,819 g in 3,785 mL, 1.0089 g/mL, 238.7 g per US cup. Food Standards Australia New Zealand's table of specific gravities, compiled from published values, gives vinegar 1.01, 239.0 g a cup. A Japanese kitchen measuring table from Kagawa Nutrition University's basic cooking data, reproduced by the city of Hiroshima, weighs vinegar at 5 g a teaspoon, 15 g a tablespoon and 200 g per 200 mL cup, 1.00 g/mL; it gives whole grams, so it cannot show the last 1%. The three agree within 1%.

USDA has no rice vinegar record, and King Arthur Baking's chart has no vinegar rows, so there is nothing to correct here.

The physical check: rice vinegar is about 95% water, with 4 to 4.5% acetic acid and a trace of sugars and other solids left from the rice. Acetic acid is denser than water, about 1.05 g/mL, and in a dilute solution it adds only a little weight; a 4 to 5% vinegar weighs about 1.005 to 1.01 g/mL. Kikkoman's 1.0089 sits at the top of that span, consistent with the small amount of rice solids. White vinegar on this site weighs 238 g a cup and apple cider vinegar 239 g, so rice vinegar sits with them.

Practical guidance: use 238.7 g per cup, 119 g per half cup, 14.9 g per tablespoon and 5 g per teaspoon. For any practical purpose rice vinegar measures like water: a tablespoon is 15 g and a quarter cup 60 g, and filling a liquid measuring cup to the line is accurate. If a recipe calls for seasoned rice vinegar and you use plain, add the sugar and salt yourself; if it calls for plain and you only have seasoned, cut back the recipe's sugar and salt. Rice vinegar keeps its flavour best in a closed bottle away from heat.