NAPS by age:

• 4 to 8 months old: 3 naps a day, Nap 1 and Nap 2 should be long while Nap 3 is considered a cat nap less than an hour.
• 8 to18 months  old: 2 naps a day,  morning and afternoon, both a minimum of 1 hour long. 
• 18mo  to 2.5 years old:  1 nap a day,  2-3 hours long. 
• 2 to 3 years old: 1 nap a day that starts to shorten in time. 

You may wonder "my baby is only 6 months old and she's  only taking 2 naps!"   All babies are different and not every child will keep her third nap. Similarly, not every child will transition to one nap  at exactly 18mo of age. As babies turn into toddlers, their brains are still developing and their sleep needs change at different ages.  You can help by tuning into their sleep cues  and periods of wakefulness.