When it involves baking, accuracy in your dimensions is an important to a recipe’s success, and the single most accurate way to measure your ingredients is through weight.

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I’ve received a few questions lately on several of my an ext popular cake recipes the seem to suggest some confusion about weight versus volume measurements, specifically when it comes to measuring dry ingredients favor flour. Ns figured I’d execute a bit much more in-depth explanation in a post, come hopefully clear up any kind of confusion.

American bakers flourished up making use of cups, wherein a cup the water is same to a cup the flour and so forth. We likewise had the drilled right into our brains the a cup is 8 ounces and also a pint is a pound the civilization round (a pint being 2 cups or 16 fluid ounces).

But I’m right here to say the a pint is NOT constantly a pound and also a cup is NOT always 8 ounces—it counts on what you’re measuring.

Now before you start arguing, permit me explain!

Weight versus Volume

Volume is a measure up of the lot of room something takes up. Things prefer cups the flour, gallons the milk, cubic feet of helium… these are all volume measurements.

Weight is a measure up of one object’s heaviness. Grams the salt, pounds the sugar, kilograms the apples… these are measurements of weight.

Ok. So, that renders sense, right? Volume and weight space measuring two entirely different things.

You’ve heard the old riddle: Which weighs more: a pound of feather or a lb of lead?

Trick question: lock both sweet a pound! however the lead is going to have actually a much smaller volume due to the fact that it is more dense than the feathers, for this reason it will certainly look favor a smaller amount that material.

When we’re talking around baking, the differences could not be rather as noticeable as feathers and also lead, however the very same is true the flour and also water: one is much less dense than the other (in this case the flour is the feathers and also the water is the lead). For this reason a lb of flour is going to take up more space, or volume, 보다 an tantamount pound the water.

An oz of Confusion

Most that the confusion concerning weight and volume dimensions occurs when talking about ounces: an imperial unit of measure which deserve to be supplied to suggest both weight and also volume. Liquid ounces refers to volume (like milliliters) whereas continuous ounces refer to weight (like grams). The truth that they room both dubbed ounces, and not constantly differentiated by saying ounce/fluid ounce is one factor why they are so problematic.

Ounces by weight and ounces by volume space ONLY equivalent when you are measuring water or other liquids with a comparable density.

For example, 8 ounces that water by weight will certainly equal 8 fluid ounces through volume.

Flour, on the various other hand, is a totally different ballgame and also a confound one come boot. No that you’d ever before measure flour with fluid ounces (which are only designed to measure—you guessed it—fluids), but, if you did, you’d find that 8 liquid ounces that flour just weighs around 4 1/4 ounces. Weigh out 8 ounces of flour through weight and also you’re going come have around 14 liquid ounces by volume. See how confusing the is?

I mean, who carry out we have to petition to have liquid ounces adjusted to be referred to as something entirely different (flounces? frams? vols?) or, better yet, finally just switch to metric choose the remainder of the world?


Here space some visual comparisons to assist illustrate this principle (keep in mind the you shouldn’t be measuring flour in a liquid measuring cup favor this, I just did so below so I could illustrate the differences between ounces by weight and also ounces through volume).


Both of these containers are holding 8 ounces.

On the left is 8 ounces that flour by weight, and on the best is 8 ounces that flour by volume (aka 1 cup).

If you sweet the 2 containers, the one on the appropriate would only weigh roughly 4 1/4 ounces.


Both of this containers room holding 8 ounces.

Weigh out 8 ounces that flour and 8 ounces of water ~ above a scale and this is what girlfriend get. Visually the looks favor you have actually a lot more flour 보다 water, yet they weigh the specific same amount.


Both of this containers are holding 8 ounces.

On the left is 8 ounces that flour by volume and also on the right is 8 ounces the water by volume. Basically, what friend see here is 1 cup of flour and 1 cup the water.

But if you placed these 2 containers on a scale, the flour top top the left would just weigh 4 1/4 ounces, if the water would weigh 8 ounces.

So, are you less confused yet? much more confused? ns don’t blame friend (lol).

My advice? once you’re baking, forget ounces entirely. Pretend castle don’t even exist. It simply confuses things. Instead, emphasis on cup/tablespoon measurements for volume, and grams for weight.

I’m trying come be better about writing my recipes using just cups and grams for this very reason, though you might still check out ounces on enlarge recipes or for things that are marketed by the ounce, like bars of coco or can be ~ of pumpkin.

Tip: when purchasing packaged or box goods, if you’re unsure whether the ounce measurement ~ above the package refers to ounces by weight or liquid ounces, look at the metric equivalent. If it’s grams (like on crate pumpkin or coco bars), you’re managing weight. If it’s liters (like on milk or wine) climate you’re taking care of fluid ounces.

The beauty, beauty of Metric

One that the beautiful things around the metric mechanism is that there is no confusion. Grams room weight, milliliters are volume. If you see grams, grab her scale. If you see milliliters, grab her liquid measuring cup.

Another genius facet of the metric mechanism is that it is calibrated to water: so once you’re measure up water or other liquids v a similar density (like milk or orange juice), 200 milliliters will certainly weigh 200 grams. Cool!

However, as soon as you begin measuring dried ingredients, which often have differing densities, the 2 numbers will certainly not match.

1 cup of water weighs 236 grams.1 cup of flour weighs 125 grams.

The volume is the same, yet the weight is different (remember: lead and also feathers).

One other advantage to using metric measurements is accuracy: scales frequently only present ounces come the 4 minutes 1 or eighth of one ounce, therefore 4 1/4 ounces or 10 1/8 ounces. Grams top top the other hand, being a much smaller unit that measurement, make it less complicated to be exceptionally precise. Exactly 236 grams the water is a much much more accurate measurement 보다 8 3/8 ounces (technically 236 grams equals 8.32466 ounces but you’re not going to have the ability to measure that on a scale). The distinction of 1/8th the an oz is 3-4 grams, which may not seem prefer much, yet it can add up.

A cup is a cup is a cup

… depending upon what you’re measuring and also how you measure it.

Liquids room pretty reliable. A cup is pretty much constantly going to it is in a cup.

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But because that dry ingredients, flour special, the small granules that flour have the right to be compacted, essentially packing much more flour right into the very same amount of an are (think about packing brown sugar, it’s a comparable idea).

So depending on how girlfriend measure your flour, if friend fluff it and spoon it right into the cup, or if you scoop directly from a bag that flour that has settled, your ‘cup’ might vary through as lot as 30% by weight, from 120 grams come upwards the 150 grams (!!) once you’re making a cake the calls for 3 cups of flour, that’s virtually an entire extra cup if you’re scooping directly from the bag. No wonder the cake is too dry…