Because of the variation in dropper insert hole sizes, the following is only a general guide:
MINIMUM– MAXIMUM DROPS OF ESSENTIAL OIL
INTO MILLILITERS OF CARRIER OIL
OR SPOON MEASUREMENTS OF CARRIER OIL
ESSENTIAL OILS DILUTION GUIDE
CONVERSIONS: OUNCES AND MILLILITERS
Very often in this website is suggested blends diluted in 1 fluid ounce (fl. oz.), or 30 mL, of carrier oil. Because of the difficulties of conversion, this is slightly inaccurate; in 1 fl. oz. there are in fact 29.5735296875 mL. If you can, try to measure in milliliters because measuring small quantities is easier in Metric than it is in Imperial. For reference, here are the conversion rates.
To convert volumes in milliliters into fluid ounces: