Methods to get file sizes in Python

The following are some of the ways you can get the size of files in Python.

Making use of OS module’s stat function

As shown in the code snippet below, the stat function is an easy way for Python to get the file size in bytes. The relative path to the file is used as an argument for the stat function which is used to obtain the statistics of the file. In the example below, a .csv file was used. However, another file of a different format can be used and the stat function will still get the file size.

''' 
  Using the OS module's stat function  
''' 
import os
file_size = os.stat('/content/sample_file.csv')
print("file size :", file_size.st_size, "bytes")

Making use of os.path module’s getsize function

Still using the OS module, the getsize function can be used in Python to get the file size. It is easy and straightforward and only requires one argument. As shown below, the file path is the argument which was used in Python to get the size of the file.

''' 
  Using the os.path module's getsize function  
''' 
import os
file_size = os.path.getsize('/content/sample_file.csv')
print("file size :", file_size, "bytes")

Making use of the pathlib module

The pathlib module is simply a wrapper for most functions in the OS module. It still uses the stat function from the module. As shown below, using the pathlib module to get the size of a file in Python still shows a consistent result.

''' 
  Using the pathlib module getsize function  
''' 
import pathlib
file_path = pathlib.Path('/content/sample_file.csv')
file_size = file_path.stat().st_size
print("file size :", file_size, "bytes")

Making use of file object

The file object can be used in Python to get the file size. This approach takes a longer approach than the previously discussed ones. To implement this, the file is first opened after which the seek method is used to set the location of the cursor. Taking two arguments, the seek method sets the cursor at the beginning and end of the file's location. Furthermore, the tell method gets the corresponding cursor location or total bytes moved by the cursor.

''' 
  Using the file object
''' 
open the file
file = open('/content/sample_file.csv')
position the cursor at the end
file.seek(0, os.SEEK_END)
use tell to get size of file
print("Size of file is :", file.tell(), "bytes")

Conclusion

Having gone through the different methods used to get the size of files in Python, you can now choose which one best works for you. It should be worth noting that the getsize function of the os.path module is the fastest, followed by the stat function. On the other hand, the file object performed the least and took more time. Knowing the speed of performance helps as the file size increases. The method to be used should be the one that gives the best performance in the least possible amount of time. This will enable you to write efficient code that optimally utilizes resources.