How to count the number of files in a directory using Python

os.listdir() will be slightly more efficient than using glob.glob. To test if a filename is an ordinary file (and not a directory or other entity), use os.path.isfile():

import os, os.path

# simple version for working with CWD
print len([name for name in os.listdir('.') if os.path.isfile(name)])

# path joining version for other paths
DIR = '/tmp'
print len([name for name in os.listdir(DIR) if os.path.isfile(os.path.join(DIR, name))])

import os

path, dirs, files = next(os.walk("/usr/lib"))
file_count = len(files)

For all kind of files, subdirectories included:

import os

list = os.listdir(dir) # dir is your directory path
number_files = len(list)
print number_files

Only files (avoiding subdirectories):

import os

onlyfiles = next(os.walk(dir))[2] #dir is your directory path as string
print len(onlyfiles)