Updated on: 6/3/2025
What Size Is a Typical Rocks Glass?
A typical Rocks Glass, also known as an Old Fashioned or lowball glass, is the workhorse of spirits-forward cocktails. These glasses are designed to comfortably fit a standard pour of spirits—either neat, over ice, or with a mixer—while showcasing the drink's color and aroma. When you reach for a Rocks Glass, you can expect a capacity that suits classic recipes and modern builds alike.
Rocks Glass Capacity in Detail
Most rocks glasses hold between 180 ml and 300 ml. The smaller end—around 180 ml or 6 ounces—is suitable for neat pours or simple spirit-and-ice combinations. The larger size, about 300 ml or 10 ounces, allows for cocktails with extra mixers or double pours in a single serving while still leaving room for large ice cubes.
Why Rocks Glass Size Matters
- Cocktail fit: Sized for drinks like the Old Fashioned, Negroni, or Whiskey Sour, with enough volume for spirit plus ice.
- Dilution control: Large-format ice cubes fit neatly inside, slowing dilution so flavors stay vibrant longer.
- Versatility: Perfect for neat spirits, on-the-rocks pours, and short cocktails calling for 90–120 ml of liquid plus ice.
Typical Rocks Glass Sizes Compared
- Small rocks glass: 180 ml (6 oz) — best for neat whiskey or spirit-forward sippers with minimal dilution.
- Standard rocks glass: 240 ml (8 oz) — ideal all-purpose size for most classic recipes with ice.
- Large rocks glass: 300 ml (10 oz) — suitable for double servings, tall cubes, or extra mixers like in a Double Old Fashioned.
Choosing the Right Size for Your Cocktails
When in doubt, an 240 ml to 300 ml glass serves nearly all short cocktails. It gives just enough room for both drink and ice, striking the right balance for classic recipes and modern interpretations that use large craft ice.
Whether you're outfitting your home bar or choosing glassware for a cocktail program, a standard rocks glass size—between 180 ml and 300 ml—covers almost every classic need while leaving room for creativity and modern ice.