What Capsule Filler Size Do You Need? Choose the Perfect Size Capsule for Your Supplement Powder

Choosing the right size capsule may seem like a difficult task, but we’ve made it easier to choose the right size for your needs.

This chart shows generally how much weight each capsule size can hold. The reason these numbers vary is because capsules hold a volume (amount of space)… not a weight. The problem is that the amount of powder each capsule size will hold is usually expressed in grams(g) or milligrams(mg)… and that changes depending on the density of that powder.

The Density Problem

To illustrate the difference between weight and volume, picture a ziplock bag full of feathers and another ziplock bag of the same size filled with sand:

• Both bags hold the same volume: This means they can both hold the same amount of space.

• Yet, the full bag of feathers weighs much less than the full bag of sand, despite holding the same volume of each.

Since the sand weighs more than the feathers do with the same volume of each, this means the sand has a higher density than feathers do.

Density is a measurement of how much substance (weight*) fits into an amount of space (volume).

*Note: For the engineers/physics sticklers, Weight is how we measure the mass of an object. Therefore we’ve replaced the term mass with weight, to simplify the meaning.

Supplement Powder Density

In this same way, one powdered ingredient may have a much higher density than another kind of powdered ingredient. A good comparison would be matcha versus creatine powder. Matcha is a fully-dissolvable powder taken from Japanese green tea leaves, while creatine is an isolated chemical substance used to enhance strength training.

Creatine typically comes in granulated crystal form or a more ground-up powder. Matcha is much lighter than creatine, which is true of most powders derived from plant matter.

This comparison demonstrates an easy general rule for determining whether your powder will be at the higher or lower range of the number of milligrams shown in the capsule-size chart above:

Plant Matter Density Rule

• Herbs, botanicals, mushrooms, and other plant matters are generally in the middle to lighter and less dense side of the range

• Pure isolated chemical/supplement powders (most commonly white in color) tend to lean toward the heavier, more dense side

If you’re having trouble determining which of the types your powder is, you can use what we coined, the float test.

But why do we want to know the density?

Because if we know the density, we know exactly how much any capsule size will hold of your powder!

The Float Test - Roughly Judge Your Powder’s Density

Take a small spoonful of your powder and pour it into a glass of water

• If your powder FLOATS in water (herbs, mushrooms, etc.) it will typically be in the mid to lighter side of each range in the chart above.

• If your powder immediately SINKS and drops down into the water (BCAAs, creatine, pre-workout, etc.), it leans toward the more dense side of the range.

Ok.. but how can you be certain of how much powder your capsule will hold? Don’t worry, we’ve got you.

Density Calculation - Finding How Much Powder each Capsule Size Holds

Density can be measured by dividing a powder’s weight by its volume. This is usually expressed as grams/milliliters (g/mL). For example, we recently weighed 1 (very tightly packed) teaspoon of a particular type of mushroom powder to be 3.3 grams. Being that 1 teaspoon is equal to 5mL in volume, we can immediately find the density of that mushroom powder by dividing 3 grams by 5 milliliters:

• 3g/5mL = 0.662g/mL is the density of the mushroom powder

  • Once we know the density, we can tell exactly how much mushroom powder will fit into each capsule size simply by referring a capsule volume chart like ours here:

• With the volume of each size, all we have to do is multiply the density of the mushroom powder by the volume of the capsule size. This will tell you exactly how many grams of mushroom powder that size will hold!

  • Here’s the calculation for each capsule size using the volume of each capsule body*:

    • Size 000 (Volume= 1.37mL): 0.662g/mL * 1.37mL = 0.907 grams = 907 milligrams

    • Size 00 (Volume= .95mL): 0.662g/mL * 0.95mL = 0.629 grams or 629 milligrams

    • Size 0 (Volume= .68mL): 0.662g/mL * 0.68mL = 0.45 grams or 450 milligrams

    • Size 1 (Volume= .5mL): 0.662g/mL * 0.5mL = 0.331 grams or 331 milligrams

    • Size 2 (Volume= .37mL): 0.662g/mL * 0.37mL = 0.245 grams or 245 milligrams

    • Size 3 (Volume= .3mL): 0.662g/mL * 0.3mL = 0.199 grams or 199 milligrams

    • Size 4 (Volume= .21mL): 0.662g/mL * 0.21mL = 0.139 grams or 139 milligrams

    • Size 5 (Volume= .1mL): 0.662g/mL * 0.1mL = 0.066 grams or 66 milligrams

    *Note: When filling capsules, you’re only supposed to fill the capsule body (the larger half). This is how capsule-filling machines work, allowing you to be certain of the dosage.

Does this look like a lot of effort? We’ve made it much easier for you! Calculate your capsule size in seconds by using our capsule size calculator!

Capsule Size Calculator:
Calculate the exact weight any capsule size will hold

Screenshot of our capsule size calculator tool