How many diapers you need depends on an approximate answer to how often your child needs diaper changing multiplied by how often you wash diapers. For example: 8 diaper changes per day times washing every 2 days = 16 diapers plus, perhaps, 6 diapers for backup. Twenty-two is a good foundation for a small but workable diapering system. You will also need a bare minimum of three diaper covers for each size: one on, one airing out, one in the wash.

How often your child needs a diaper change depends on age, whether she is breastfed, and her own physiology. Not all of that is easy to anticipate, but the rule of thumb seems generally to be that the average newborn needs a new diaper every two hours, including some nighttime changes. You would want to start with 12 diapers a day for a newborn. If you wash every other day you will need a minimum of two dozen diapers. In practice, you may not want to wash as frequently, but equally you may not change your baby's diaper as often as every two hours. An Extra Small Firefly Diaper will fit most newborns, but only for a short time. For a newborn, you may want to buy fewer diapers and wash more frequently. Some newborns can start with the Small size, which should fit for quite a while. In this case, you may want to have more diapers to create a more flexible diapering and washing system. Three dozen is a good number of diapers to have in Small.

Once your baby is sleeping through the night, the nighttime changes may stop. Now you may only need about 6-8 diapers per day and your baby may be ready for a larger diaper. Two dozen diapers and four covers would be a good number to have on hand. If your baby fits a Medium Firefly at this point, you may not need to buy the Large size before your child leaves diapers. Only the largest child will need a Large Firefly, and few toddlers need to move on to Extra Large.

By the time your child is showing some interest in using the toilet, at least some of the time, she may tell you when she is wet or even before she is wet. You may not have many diapers actually go into the diaper pail. You may need one diaper for nighttime and 4-6 changes during the day. If you are still using Medium Firefly Diapers, you probably won't reach down to the bottom of your diaper stash each wash cycle.

Even when your child is using the toilet exclusively during the daytime, she may still need a nighttime diaper. Some children will still be wearing Medium; some may need a few Large Firefly Sleep Tight diapers. At this point 2-3 diapers and a cover are probably all you will need.

Adjust the numbers and sizes to suit yourself and your child, but you may need:

• 12 Extra Small Quick Dry diapers, plus 1 Sleep Tight diaper for nighttime
• 9 Small Quick Dry diapers, plus 1 Sleep Tight diaper for nighttime
• 6 Medium Quick Dry diapers, plus 1 Sleep Tight diaper for nighttime
• 3 Large Quick Dry diapers, plus 1 Sleep Tight diaper for nighttime

• x the number of days between washes
• + a few extras for emergencies (flat diapers are good for this)
• = the diaper foundation of your cloth diapering system

Add 3-4 covers in each size, and you will find you need little more to start cloth diapering your child.