4 oz = 113 grams (weight) or 120ml (liquid volume). The conversion depends on whether the recipe is measuring weight (oz for ounces) or fluid volume (fl oz for fluid ounces).
If you're following an American recipe or nutrition label, you'll often see measurements in "ounces" (oz). In the UK, we use grams for weight and millilitres for liquids, so you need to convert.
This guide explains exactly how much 4 oz is and provides a full conversion table for cooking and calorie tracking.
An ounce (oz) is an imperial unit of measurement used in the US and older UK recipes. There are two types:
Important: Most modern recipes use US fluid ounces (29.57ml). When you see "4 oz" in a recipe, check the context:
4 oz = 113.4 grams (round to 113g or 115g)
Common uses:
4 fl oz = 118ml (round to 120ml)
Common uses:
| Ounces (oz) | Grams (g) | Common Use |
|---|---|---|
| 1 oz | 28g | Small portion of cheese |
| 2 oz | 57g | Handful of nuts |
| 3 oz | 85g | Deck of cards (meat portion) |
| 4 oz | 113g | Standard chicken breast portion |
| 5 oz | 142g | Large chicken breast |
| 6 oz | 170g | Salmon fillet |
| 8 oz | 227g | ½ pound (half lb) |
| 12 oz | 340g | Can of fizzy drink |
| 16 oz | 454g | 1 pound (1 lb) |
| Fluid Ounces (fl oz) | Millilitres (ml) | Common Use |
|---|---|---|
| 1 fl oz | 30ml | Shot glass |
| 2 fl oz | 60ml | Small juice glass |
| 4 fl oz | 120ml | ½ cup |
| 6 fl oz | 180ml | ¾ cup |
| 8 fl oz | 240ml | 1 cup / small glass |
| 12 fl oz | 355ml | Standard can of fizzy drink (US) |
| 16 fl oz | 473ml | 1 pint (US) / large glass |
| 32 fl oz | 946ml | 1 quart (US) |
Formula: Multiply ounces by 28.35
Examples:
Quick mental math: 1 oz ≈ 30g (close enough for cooking)
Formula: Multiply fl oz by 29.57 (or use 30 for simplicity)
Examples:
Quick mental math: 1 fl oz ≈ 30ml
The UK adopted the metric system in the 1960s-70s for several reasons:
No. 4 oz = 113g (weight), while 4 fl oz = 120ml (liquid volume). They're different units measuring different things.
4 fl oz = ½ cup (120ml). For dry ingredients measured by weight, it depends on density (see our guide: How Many Grams Is 1 Cup?)
4 oz (113g) of chicken breast is roughly the size of a deck of cards or the palm of your hand (without fingers).
It depends:
If you're counting calories or macros with an app like NutraSafe, always measure in grams for accuracy. UK food labels show nutrition per 100g, making it easy:
Example: 4 oz (113g) of chicken breast
Ounce measurements are less precise for tracking.
To estimate 4 oz (113g) without scales:
Best practice: Use digital kitchen scales (£10-15 on Amazon) for accurate measurements.
| System | Weight | Liquid Volume |
|---|---|---|
| US (Imperial) | Ounces (oz), pounds (lb) | Fluid ounces (fl oz), cups, pints |
| UK (Metric) | Grams (g), kilograms (kg) | Millilitres (ml), litres (L) |
| Conversion | 1 oz = 28.35g | 1 fl oz = 29.57ml |
4 oz = 113 grams (weight) or 120ml (liquid). Use the conversion tables above when following American recipes, or invest in digital kitchen scales to measure everything in grams for perfect results every time.
Quick reference:
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← Back to BlogLast updated: February 2026