Split
What is a split of wine?
A split is a small wine bottle, especially common for sparkling wine and hospitality service. In the United States, the current TTB standards-of-fill list includes 187 mL. That is about 6.3 U.S. fluid ounces, or 1.26 five-ounce volume units.
You may see 187.5 mL in casual charts because it is exactly one quarter of 750 mL. It is not the number on TTB’s current U.S. authorized-fill list. The Comité Champagne uses another convention again: its official quarter is 200 mL. The practical rule is to use the printed net contents rather than assume that every “split” or “quarter” is identical.
For the complete capacity comparison, regional naming caveats, and calculation method, use the wine bottle sizes chart.
Sources: TTB wine net contents; Comité Champagne bottle-size FAQ.