Getting file size in Python?

594
votes

Is there a built-in function for getting the size of a file object in bytes? I see some people do something like this:

def getSize(fileobject):
    fileobject.seek(0,2) # move the cursor to the end of the file
    size = fileobject.tell()
    return size

file = open('myfile.bin', 'rb')
print getSize(file)

But from my experience with Python, it has a lot of helper functions so I'm guessing maybe there is one built-in.

4
pythonfilesize
Path('./doc.txt').stat().st_size - Boris

4 Answers

846
votes

Use os.path.getsize(path) which will

Return the size, in bytes, of path. Raise OSError if the file does not exist or is inaccessible.

import os
os.path.getsize('C:\\Python27\\Lib\\genericpath.py')

Or use os.stat(path).st_size

import os
os.stat('C:\\Python27\\Lib\\genericpath.py').st_size

Or use Path(path).stat().st_size (Python 3.4+)

from pathlib import Path
Path('C:\\Python27\\Lib\\genericpath.py').stat().st_size
234
votes
os.path.getsize(path)

Return the size, in bytes, of path. Raise os.error if the file does not exist or is inaccessible.

94
votes

You may use os.stat() function, which is a wrapper of system call stat():

import os

def getSize(filename):
    st = os.stat(filename)
    return st.st_size
25
votes

Try 

os.path.getsize(filename)

It should return the size of a file, reported by os.stat().