Could Callahan be the perfect name for your baby boy? The baby boy name Callahan is 8 letters long, and contains 3 vowel(s) and 5 consonant(s). Callahan is a baby boy name that starts with the letter C and ends in the letter N. The baby boy name Callahan has a popularity of 11% and is ranked 892 in the list of top 1000 most popular baby boy names. If Callahan isn't the ideal name for your baby boy then take a look here for some randomly generated names. Hopefully you'll find a more suitable first name for your baby boy than Callahan!