Cooking Measurements & Recipe Conversions: The Complete Guide
Cooking is the most international hobby on Earth — and probably the most poorly-standardized. A French baker measures flour to the gram. An American baker measures it in cups. A British baker uses fluid ounces but a different fluid ounce than the American. The oven gets set in Celsius, Fahrenheit, or one of nine "gas marks" depending on which country sold you the cookbook. And nobody can agree on whether "1 tablespoon" means 15 mL, 14.8 mL, 20 mL, or 17.7 mL.
This guide will walk you through every conversion you actually need in the kitchen: cups to grams (and why this is harder than it sounds), US to UK to metric volumes, the three major oven scales, the egg size question, and the calorie math behind food and exercise. By the end you'll be able to bake an English recipe in a Californian kitchen, or a French one in a Sydney apartment, without disaster.
If you need a quick answer mid-recipe, jump to the cooking converter or oven converter. For everything else, read on.
Why Cooks Need to Convert in the First Place
The world has split into two large cooking traditions:
| Region | Dry ingredients | Liquid ingredients | Oven |
|---|---|---|---|
| USA, Canada (informal) | Volume (cups, tbsp) | Volume (cups, fl oz) | Fahrenheit |
| Europe, most of Asia, AU/NZ | Mass (grams) | Volume (mL, L) | Celsius |
| UK | Mix — old recipes use oz, new use g | Mostly mL | Celsius or gas marks |
The American approach treats flour the same as milk: measure it in a cup. The European approach insists that dry ingredients must be weighed because a "cup of flour" can vary by 30% depending on how packed it is.
Professional bakeries everywhere — including in America — use mass because it's the only consistent way to scale a recipe. Home cooks lean on volume for convenience.
💡 Fun fact: The "cup" as a kitchen measure was popularized in 1896 by Fannie Farmer in The Boston Cooking-School Cook Book. Before that, American recipes routinely said things like "a butter the size of a walnut" or "flour enough to make a stiff dough."
Volume vs Mass — The Density Problem
The reason cup-to-gram conversion isn't a simple lookup is density. A cup of feathers and a cup of lead weigh wildly different amounts. The same goes for flour vs sugar vs water.
Quick reference for 1 US cup (240 mL):
| Ingredient | Grams per cup |
|---|---|
| Water | 240 g |
| Milk | 245 g |
| Sugar (granulated) | 200 g |
| Brown sugar (packed) | 220 g |
| Powdered sugar | 120 g |
| All-purpose flour (sifted) | 120 g |
| All-purpose flour (scooped) | 150 g |
| Bread flour | 130 g |
| Butter | 227 g |
| Honey | 340 g |
| Rolled oats | 90 g |
| Cocoa powder | 100 g |
| Salt | 290 g |
A single cup of flour can vary from 120 g to 150 g depending on whether you spoon it lightly into the cup or pack it down. This is the single biggest source of baking failure for home cooks switching between volume and mass recipes. Always use a kitchen scale for baking when accuracy matters.
The cooking converter handles these density-aware conversions for the most common kitchen ingredients.
US Cup vs Imperial Cup vs Metric Cup
There are three different cups in widespread use:
| System | Size |
|---|---|
| US legal cup | 240 mL |
| US customary cup | 236.588 mL |
| Imperial (UK) cup | 284.131 mL |
| Metric cup (AU/NZ/Canada) | 250 mL |
The US legal cup (240 mL) is what's printed on nutrition labels. The US customary cup (about 237 mL) is what most American recipes actually use. The Imperial cup is 18% larger than the US cup — which means an Imperial recipe scaled by volume into US cups will undershoot every measurement.
Most modern UK recipes use grams and mL, sidestepping the issue. But older British cookbooks (pre-1970s) use Imperial cups, fl oz, and pints — and those numbers don't directly translate.
| US measure | mL |
|---|---|
| 1 tsp | 4.93 |
| 1 tbsp | 14.79 |
| 1/4 cup | 59 |
| 1/3 cup | 79 |
| 1/2 cup | 118 |
| 1 cup | 237 |
| 1 pint | 473 |
| 1 quart | 946 |
| 1 gallon | 3785 |
| UK measure | mL |
|---|---|
| 1 tsp | 5.92 |
| 1 tbsp | 17.76 |
| 1/2 pint | 284 |
| 1 pint | 568 |
| 1 quart | 1136 |
| 1 gallon | 4546 |
A UK pint is 20% larger than a US pint — important if you're following a British beer or cocktail recipe.
Oven Temperatures — Three Scales to Juggle
Ovens come in three different temperature dialects:
| Description | °C | °F | Gas Mark |
|---|---|---|---|
| Very cool | 110 | 225 | 1/4 |
| Cool | 130 | 250 | 1/2 |
| Warm | 140 | 275 | 1 |
| Slow | 150 | 300 | 2 |
| Moderate (slow) | 170 | 325 | 3 |
| Moderate | 180 | 350 | 4 |
| Moderate (hot) | 190 | 375 | 5 |
| Hot | 200 | 400 | 6 |
| Very hot | 220 | 425 | 7 |
| Very hot | 230 | 450 | 8 |
| Extremely hot | 240 | 475 | 9 |
Gas marks are a uniquely British scale from the era when most domestic ovens were gas-powered with simple knobs labeled 1–9. Each gas mark step is about 14 °C (25 °F). Convection (fan-forced) ovens should typically be set 20 °C lower than the recipe states, because moving air transfers heat more efficiently.
The oven converter cross-references all three with a quick-reference table.
💡 Fun fact: Many older Indian and East African home cooks still describe oven temperature by feel — "hot enough that a piece of paper browns in 10 seconds" was a real recipe instruction in Mrs Beeton's Book of Household Management from 1861.
Tablespoons and Teaspoons — Not as Standard as You Think
Even at the small-spoon end, the world disagrees:
| System | 1 tsp | 1 tbsp |
|---|---|---|
| US | 4.93 mL | 14.79 mL |
| Metric | 5 mL | 15 mL |
| UK (post-1990s) | 5 mL | 15 mL |
| Australia | 5 mL | 20 mL |
| Japan | 5 mL | 15 mL |
The big outlier is Australia's 20 mL tablespoon. An Australian recipe calling for "1 tbsp olive oil" wants 33% more than an American recipe does. If you're cooking from an Aussie cookbook in the US, scale tablespoons up by a third (or measure in mL instead).
The Egg Size Confusion
Recipes call for "1 egg" as if eggs were a standard unit. They aren't. Egg sizes vary by country:
| Size | US (per egg, g) | EU (per egg, g) |
|---|---|---|
| Small | 38–42 | Below 53 |
| Medium | 50 | 53–63 |
| Large | 57 | 63–73 |
| Extra Large | 64 | Above 73 |
| Jumbo | 70+ | — (EU caps at XL) |
A US large egg ≈ an EU medium. If a French recipe says "3 oeufs" and you're using US large eggs, use 3 — but if you're using US extra-large or jumbo, drop to 2.5. This matters most in baking, where the moisture content of eggs is part of the structural balance.
Calories — kcal vs kJ vs Joules
Food labels around the world report energy in either kcal (kilocalories) or kJ (kilojoules).
1 kcal = 4.184 kJ
1 kJ = 0.239 kcal
The confusing bit: when American food labels say "calories," they mean kilocalories. So a "300 calorie" snack bar is actually 300,000 calories in the strict scientific sense (300 kcal). The lowercase "calorie" is essentially defunct outside chemistry textbooks; in food, "Calorie" (capital C) and "kilocalorie" mean the same thing.
| Energy | kcal | kJ |
|---|---|---|
| Apple (medium) | 95 | 397 |
| Banana | 105 | 439 |
| Slice of bread | 80 | 335 |
| Egg (large) | 70 | 293 |
| Mars bar | 230 | 962 |
| Big Mac | 540 | 2,260 |
| 1 g fat | 9 | 37.7 |
| 1 g protein | 4 | 16.7 |
| 1 g carbohydrate | 4 | 16.7 |
| 1 g alcohol | 7 | 29.3 |
Australia and the EU label primarily in kJ; the US and UK label in kcal. The calorie converter handles both, plus a food reference list and a calorie-burn-by-activity calculator.
Calorie Burn — The MET System
How many calories do you actually burn running? The standard answer uses MET — Metabolic Equivalent of Task. 1 MET is the energy you burn sitting still (~1 kcal per kg of bodyweight per hour).
Calories burned = METs × weight (kg) × duration (hours)
Some MET values:
| Activity | METs |
|---|---|
| Sleeping | 0.9 |
| Sitting | 1.0 |
| Walking (3 mph) | 3.5 |
| Cycling (leisurely) | 4.0 |
| Jogging | 7.0 |
| Running (6 mph) | 9.8 |
| Swimming (vigorous) | 10.0 |
| Boxing (sparring) | 9.0 |
| HIIT class | 12.0 |
| Skipping rope | 12.3 |
So a 70 kg person running for 30 minutes burns: 9.8 × 70 × 0.5 = 343 kcal. The calorie burn calculator does this for dozens of activities.
💡 Fun fact: Fitness trackers can be off by 20-30% when estimating calorie burn — they don't know your true metabolic rate, body composition, or efficiency. The MET formula tends to be more reliable for steady-state activities than wrist-based heart rate inference.
Scaling Recipes
Doubling or halving a recipe isn't always linear:
- Seasonings (salt, spices, herbs): scale by about 75% of the multiplier. Doubling a recipe means using 1.75x the salt, not 2x.
- Baking time: doesn't scale linearly. Doubling a cake recipe might mean only 30% more bake time.
- Pan size: scale by volume, not surface. A pan twice as wide (in both dimensions) holds 4x the volume.
The cooking converter helps with the unit math; the seasoning and bake-time intuition you'll develop with practice.
Putting It Together — Baking an Italian Recipe in an American Kitchen
A traditional Italian torta della nonna might call for:
- 300 g flour → about 2.5 US cups (sifted)
- 200 g sugar → 1 US cup
- 180 °C oven → 350 °F or Gas Mark 4
- 3 medium eggs (EU) → 3 large eggs (US)
- 100 mL milk → 1/2 cup minus 1 tbsp
The whole recipe converts cleanly in about a minute with the right tools. For a deeper dive into volume vs mass measurement, see our companion guide Cups vs Grams.
FAQ
Should I always weigh ingredients? For baking, yes — accuracy matters when leavening, gluten development, and moisture balance are at stake. For everyday cooking (soups, stir-fries, sauces), volume is fine. A kitchen scale costs $15 and pays for itself in better bakes.
Why is American "1 cup" different from a real cup in my cupboard? Because the kitchen "cup" is a defined measure (240 mL US legal, 237 mL US customary) — not the same as the beverage vessels in your kitchen, which range from 200 mL espresso cups to 500 mL mugs. Always use measuring cups for recipes.
Can I use volume for flour in baking? You can, but expect 10–20% variability. If a recipe gives both, prefer the mass figure. If only volume is given, spoon and level (don't scoop): spoon flour into the cup, then level off with a knife. Scooping packs the flour and gives you ~25% extra.
Are calories on food labels accurate? US FDA allows ±20% tolerance on calorie labels. Most products are within 10% but a few have been caught at 30–40% over. Whole foods (an apple, an egg) have more reliable estimates than processed products.
Why is the Australian tablespoon so big? Historical accident. Australia standardized on a 20 mL tablespoon in 1973 when it metricated, choosing it as four 5 mL teaspoons for cleanness. The rest of the world either kept the 15 mL tablespoon or rounded the 14.79 mL US tablespoon up to 15.
Related guides
- Blog: Cups vs Grams — When Volume Fails Bakers — why density matters and which recipes can survive sloppy measuring.
- Converter: Cooking Converter — cups, mL, tbsp, tsp, oz, grams.
- Converter: Oven Temperature Converter — °C / °F / Gas Mark side by side.
- Converter: Calorie Converter — kcal/kJ + food list + activity burn.
- Converter: Temperature Converter — all four temperature scales.
- Converter: Weight Converter — kg, lb, oz, g.
- Quick conversions:
The next time you stare at a recipe written in someone else's units, you'll have a complete toolkit to translate it without losing the soul of the dish.