Ounces vs Grams

Differences, use cases, and when to use each

Ounces (oz) are the imperial unit of weight for small quantities (1 oz = 28.35g). Grams are the metric unit. Cooking and food labels use both globally; science and international trade use grams exclusively.

Quick Comparison

FeatureOuncesGrams
SystemImperialMetric (SI)
1 Unit =28.35 grams0.035 ounces
UsageUS cooking, food portionsWorldwide, science, international food labels
Common UseRecipes in US cookbooksInternational recipes, nutrition facts
SubdivisionFluid oz vs weight oz (confusing)Clean decimal (milligrams, kilograms)

When to Use Each

When to Use Ounces

Use ounces for US recipe measurements, portion sizing for American consumers, and food packaging intended for the US market.

When to Use Grams

Use grams for international recipes, scientific measurements, baking precision (grams are more accurate for baking than volumetric measurements), and nutrition labels.

Pros & Cons

Ounces

US recipe compatibility
Familiar for American consumers
Confusing (fluid oz vs weight oz)
Non-decimal fractions

Grams

International standard
Decimal system
More precise for baking
Worldwide nutrition labeling
Less familiar to US consumers

Verdict

1 oz = 28.35g. Grams are more precise for cooking (especially baking) and are internationally understood. US cooks increasingly prefer grams for baking due to their precision.

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