Fluid Ounces to Grams
8 fl oz
= 240g (water) = 1 cup
⚠️ Varies by Liquid
See chart below for different liquids
Fluid Ounces to Grams by Liquid Type
| Liquid | 1 fl oz | 4 fl oz | 8 fl oz (1 cup) | 16 fl oz (2 cups) |
|---|---|---|---|---|
| Water | 30g | 120g | 240g | 480g |
| Milk (whole) | 30g | 121g | 242g | 484g |
| Heavy Cream | 30g | 119g | 238g | 476g |
| Vegetable Oil | 27g | 109g | 218g | 436g |
| Olive Oil | 27g | 109g | 218g | 436g |
| Honey | 43g | 170g | 340g | 680g |
| Maple Syrup | 39g | 156g | 312g | 624g |
| Corn Syrup | 42g | 168g | 336g | 672g |
Why Different? Each liquid has a different density. Honey is heavier (340g per 8 fl oz) while oil is lighter (218g per 8 fl oz).
Fluid Ounces vs Weight Ounces
💧 Fluid Ounces (fl oz)
- • Measures volume (space occupied)
- • Used for liquids: water, milk, oil, juice
- • 8 fl oz = 1 US cup (always)
- • Symbol: fl oz or fl. oz.
- • Measuring tool: Liquid measuring cup
⚖️ Weight Ounces (oz)
- • Measures weight (heaviness)
- • Used for solids: flour, sugar, butter
- • 1 oz = 28.35 grams (always)
- • Symbol: oz or oz. wt.
- • Measuring tool: Kitchen scale
⚠️ Common Mistake: 8 fl oz water = 240g, but 8 oz weight = 227g. They're NOT the same!
Quick Fluid Ounce Conversions
1 fl oz
30g (water)
2 tbsp
2 fl oz
60g (water)
¼ cup
4 fl oz
120g (water)
½ cup
8 fl oz
240g (water)
1 cup
Formula (water): fl oz × 30 = grams (approximate)
Common Recipe Measurements in Fluid Ounces
Baking Liquids
- • 1 cup milk: 8 fl oz (242g)
- • ½ cup water: 4 fl oz (120g)
- • ¼ cup oil: 2 fl oz (55g)
- • 1 cup heavy cream: 8 fl oz (238g)
- • 2 tbsp honey: ⅔ fl oz (43g)
- • ¼ cup maple syrup: 2 fl oz (78g)
Beverage Sizes
- • Coffee cup: 6-8 fl oz
- • Water bottle (small): 16.9 fl oz (500ml)
- • Can of soda: 12 fl oz (355ml)
- • Juice box: 6-8 fl oz
- • Sports drink: 20 fl oz (591ml)
- • Wine glass (standard): 5 fl oz
How to Measure Fluid Ounces
📏 Use Liquid Measuring Cup
Clear glass or plastic cup with spout and measurement lines.
- Place cup on flat, level surface
- Pour liquid slowly
- Bend down to read at eye level (not from above!)
- Bottom of meniscus (curve) should touch the line
⚖️ Weigh on Kitchen Scale (Most Accurate)
For precision, convert fl oz to grams and weigh:
- Place bowl on scale, press "tare" to zero
- Pour liquid until scale reads target grams
- Example: 8 fl oz water = 240g on scale
Density Chart: Why Liquids Vary
Density = grams per fluid ounce (g/fl oz)
Water: Baseline density
30.0 g/fl oz
Milk: Slightly denser (fat + protein)
30.3 g/fl oz
Oil: Less dense (floats on water)
27.3 g/fl oz
Honey: Very dense (thick syrup)
42.5 g/fl oz