Measurements for Essential Oils
When working with small quantities of essential oils for your own personal use, the easiest way to measure is by the drop. Unfortunately, one drop of one essential oil may be bigger or smaller than another because of the viscosity and temperature of the oil and the size of the dropper or orifice reducer. As such, measuring by the drop is not the most accurate method of measuring essential or carrier oils, but it is generally okay for creating small topical blends and recipes for your own, individual use.
The most accurate way of measuring essential oils and formulating is by weight, not by-the-drop or by volume. To access a helpful measurement calculator that converts between various metric and U.S./British measurements, visit the Weight and Mass Converter.
Having said that, a lot of individuals are more accustomed/comfortable formulating using volumetric measurements as measuring by volume is often (but not always) quicker than weighing out ingredients. Below is a chart that shows approximate conversions between volumetric measurements. The below measurements are approximations. As touched on above, measurements regarding drops is not the most reliable and can vary greatly and is especially dependent on the viscosity (thickness) of the oil and the dropper or orifice reducer used.
20 drops ..... 1 ml
75 drops ..... 1 teaspoon
75 drops ..... 1 dram
600 drops ..... 1 ounce
15 ml ..... 1/2 ounce (.5 ounce)
1 dram ..... 1/8 ounce (.125 ounce)
1 dram ..... 3.7 ml
1 ml ..... .033 ounce
1 ml ..... .27 dram
3 teaspoons ..... 1 tablespoon
16 tablespoons ..... 1 cup
1 cup ..... 8 ounces
2 cups ..... 1 pint
4 cups ..... 1 quart
4 quarts ..... 1 gallon
For more information on measurements and to access a helpful measurement calculator, visit the Measurements Converter site.