Cooking an American Recipe in a Metric Kitchen, Start to Finish

An American recipe written for an American kitchen assumes a few things without saying so. It assumes measuring cups and spoons of a particular size, butter sold in sticks, yeast sold in packets, an oven with no fan dialled in Fahrenheit, and a 9×13-inch pan. Cook it in Manchester, Melbourne or Munich and every one of those assumptions breaks, though rarely all at once in an obvious way. Usually one of them breaks quietly, and the result is a dense loaf or a tray that overflows.

Each conversion on its own is already covered on this site. This post is about running them together on one real recipe, in an order that doesn’t make you redo any step. The recipe is a classic cinnamon roll, chosen because it hits every problem at once: cups of flour, sticks of butter, a packet of active dry yeast, an oven temperature in °F, and a pan size most European kitchens don’t own.

The recipe as an American would write it

Dough
1 cup whole milk, warmed
1 packet (2¼ tsp) active dry yeast
½ cup granulated sugar
1 stick butter, melted
2 large eggs
4½ cups all-purpose flour
1 tsp salt

Filling
¾ cup packed light brown sugar
2 tbsp ground cinnamon
½ stick butter, softened

Bake at 375°F in a greased 9×13-inch pan, 25–30 minutes.

Nothing on that card is unusual to an American cook. Almost every line needs some translation for anyone else.

Step one: get every ingredient into grams before you touch anything else

Convert first and do everything else in grams. That way nothing downstream has to multiply a fraction of a cup. The Cups to Grams converter gives these weights, all at its default spooned-and-levelled setting:

US line	Grams	Notes
1 cup whole milk	245 g	Or 240 ml; milk is close enough to water by volume
½ cup granulated sugar	100 g
1 stick butter	113 g	A stick is ½ cup; the tool shows 114 g for ½ cup butter, the wrapper says 113 g
2 large eggs	about 100 g	Not in the tool; see below
4½ cups all-purpose flour	563 g	The one line where technique moves the answer
¾ cup packed brown sugar	160 g
2 tbsp ground cinnamon	16.5 g
½ stick butter	56.8 g	Enter ¼ cup

The converter has no “stick” unit, so treat a stick as half a cup. In the US a stick of butter is 4 oz, which is 113 g, and the wrapper is marked off in eight tablespoons. When an American recipe says “1 cup (2 sticks) butter”, it means 227 g.

Two lines need more than a lookup. Flour is the ingredient where the cup lies most, and which ingredients actually need the scale explains why dip-and-sweep runs heavy and what the converter’s packed and sifted settings mean. Salt is the other. “1 tsp salt” in an American recipe usually means Diamond Crystal kosher salt, which weighs half as much per spoon as fine table salt. The same post has the salt rule and the per-teaspoon weights. Pick the right entry in the converter before you trust the number.

Eggs aren’t in the converter, and that’s the line where names mislead. An American “large” egg is graded at about 57 g in the shell, roughly 50 g once cracked. A UK or EU “large” egg is graded at 63–73 g, so it’s noticeably bigger. Medium (53–63 g) is the closer match. If you only have large eggs, beat them and weigh out 100 g.

For where the gram figures come from in the first place, the complete cups-to-grams guide has the density table. Nothing here changes it.

Your cups and spoons might not be American ones

Plenty of non-American kitchens own a set of cups, which is how this step goes wrong. Measuring spoons and cups are sized differently around the world, and the difference isn’t always small:

Measure	US	UK, Canada, NZ (metric)	Australia
Cup	236.6 ml	250 ml	250 ml
Tablespoon	14.8 ml	15 ml	20 ml
Teaspoon	4.9 ml	5 ml	5 ml

A 250 ml cup is about 6% bigger than an American one. That’s tolerable for milk and annoying for flour. The Australian tablespoon is the dangerous one. It holds four teaspoons, not three, so “2 tbsp cinnamon” measured with an Australian spoon puts in a third more than the recipe intended. On cinnamon that’s a stronger filling. On baking soda or salt it ruins the bake.

The converter’s spoon options are 15 ml and 5 ml, and its cup is 240 ml. If you’re measuring with Australian spoons, or working from an Australian recipe, set the unit to millilitres and enter 20 ml per tablespoon. Better still, convert to grams once and put the spoons away.

Step two: swap the yeast before you scale

Supermarkets outside North America often stock instant yeast in sachets or fresh yeast in blocks, not American active dry packets. A US packet is ¼ oz, which is 7 g or 2¼ teaspoons. The Yeast Converter takes 7 g of active dry and returns 14 g of fresh or 4.67 g of instant. Enter “2.25 tsp” active dry and you get 6.98 g, because the converter counts 3.1 g per teaspoon of dry yeast, so the two routes agree.

There’s one trap here. The cups-to-grams converter also lists active dry yeast, and it works at 3.5 g per teaspoon. That gives 7.9 g for the same 2¼ tsp. For yeast, use the yeast converter’s figure. It matches the 7 g printed on the packet.

The method changes too. Instant goes straight into the flour, while active dry wants warm liquid first. The reasoning and the activation temperatures are in the yeast substitution guide. For this recipe, the warm milk does the proofing either way.

Step three: fit the recipe to the tin you actually own

A 9×13-inch pan is the default American bake dish, and it’s 117 square inches, or 755 cm². European kitchens are full of tins that are close to that size but not equal to it, and here “close” decides whether the rolls bake through or overflow. What carries over from one tin to another is base area at the same depth. So the multiplier is a ratio of areas, not of side lengths:

multiplier = area of your tin ÷ area of the recipe's pan

US pan	Area	Common metric tin	Area
8×8 in square	413 cm²	20 cm square	400 cm²
9×9 in square	523 cm²	23 cm square	529 cm²
9×13 in	755 cm²	23×33 cm	759 cm²
9×13 in	755 cm²	20×30 cm traybake	600 cm²
9 in round	410 cm²	23 cm round	415 cm²
8 in round	324 cm²	20 cm round	314 cm²

For a round tin the area is 3.14 × radius². A 20 cm round is 3.14 × 10 × 10 = 314 cm². Measure the inside of the base, not the rim.

The 23×33 cm tin is a straight swap, with a multiplier of 1. The very common British 20×30 cm traybake tin is not: 600 ÷ 755 = 0.79. Put the whole recipe in that tin and you get rolls a fifth taller, raw in the centre when the tops are done. Scale to 0.8 instead. Two 20 cm round tins give 628 ÷ 755 = 0.83, which works just as well.

Step four: scale the gram version, not the cup version

Now paste the gram list into the Recipe Scaler, type 0.8 into the multiplier box, and leave the metric toggle off. Scaling grams rather than cups is the reason step one came first. Look at what the scaler would do to the original card at 0.8:

¾ cup packed light brown sugar       →   ⅝ cup packed light brown sugar
1 stick butter, melted               →   ¾ stick butter, melted
1 packet (2¼ tsp) active dry yeast   →   ¾ packet (2¼ tsp) active dry yeast
4½ cups all-purpose flour            →   3 ¼½ cups all-purpose flour

The first two are arithmetically fine and hard to measure. Nobody owns a ⅝-cup measure, and “¾ stick” is a guess with a knife. The yeast line scaled the packet and left the teaspoons alone, because the scaler only reads the first number on a line. The flour line is plain wrong. The scaler reads “4½” as a 4 followed by some text, scales the 4 to 3¼, and leaves the ½ stuck on the end. Typed as 4 1/2 it comes out as 3⅝, which is correct but no easier to measure.

The gram version comes back as 450 g flour, 90 g butter, 128 g brown sugar, 196 g milk, 80 g sugar, 13 g cinnamon, 45 g softened butter and 80 g beaten egg. You can weigh all of that straight into a bowl.

Don’t reach for the scaler’s Convert imperial → metric toggle to skip step one. It turns cups into millilitres at 240 ml each, not into grams, so 4 1/2 cups of flour becomes “1080 ml all-purpose flour”, which is no use on a scale. The line-parsing guide covers the toggle’s other side effect: with it on, bake temperatures get multiplied too.

One line needs a hand edit afterwards. The scaler rounds weights to whole grams, so 7 g of yeast at 0.8 comes back as 6 g. The real figure is 5.6 g of active dry, or 11.2 g of fresh, or 3.7 g of instant if you’re also changing the yeast type. The difference is small in a 450 g dough, but if your scale reads tenths, use them.

Step five: the oven, which is the one step you never multiply

375°F goes into the Oven Temperature Converter as 191°C, gas mark 5, and 171°C for a fan oven. Many, probably most, ovens in UK, European and Australian kitchens are fan ovens. American recipes are written for conventional ovens unless they say “convection”, so the fan figure is the one to use. Set 170°C fan, or 190°C if you switch the fan off, or gas 5.

The oven temperature guide explains the formula, where gas marks come from and why fan ovens get 20°C taken off. One thing to know about the tool: if you set it to “fan” and read the gas mark, it gives the mark for the fan temperature (gas 4 here), because it applies the offset first. Gas ovens don’t have fans, so for a gas oven read the mark with the oven type set to conventional.

Bake time barely moves with the scaled-down tin, because the depth was held constant. That was the point of scaling by area. Start checking five minutes early anyway. A fan oven and an unfamiliar tin are two unknowns, and rolls are done when the centre ones read about 88–90°C inside or spring back when pressed.

What doesn’t translate by number

Some lines need a different product rather than a conversion:

• All-purpose flour is closest to UK plain flour, which tends to run slightly lower in protein. For an enriched dough like this one it’s fine. Swapping a quarter of it for strong bread flour gives a chewier roll.
• Self-rising flour in the US contains salt as well as raising agent. UK self-raising flour doesn’t. Don’t substitute one for the other without adjusting the salt.
• Heavy cream is about 36% fat. UK whipping cream is the closer match, while double cream is richer and can split if you boil it.
• Light brown sugar maps to UK light soft brown, and confectioners’ sugar is icing sugar. Cornstarch is what the UK calls cornflour. The converter’s “Cornstarch / corn flour” entry means that one, not fine cornmeal.

Grams first, oven last

Done in this order, no step undoes another. You never multiply a cup fraction, and the oven temperature never goes near a multiplier. Start with the Cups to Grams converter for the ingredient list and the Yeast Converter for the packet. Take the gram version to the Recipe Scaler with your tin’s area ratio in the multiplier box, then finish at the Oven Temperature Converter with the oven type set to match your own oven.