How do I get the size of a file in Python?
11 Answers
Use os.path.getsize
:
>>> import os
>>> os.path.getsize("/path/to/file.mp3")
2071611
The output is in bytes.
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193Note: the implementation of
os.path.getsize
is simplyreturn os.stat(filename).st_size
– wimCommented Mar 21, 2013 at 11:20 -
1So is there a minute performance loss from using os.path.getsize as opposed to os.stat(file).st_size? Commented May 18, 2015 at 1:45
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12
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8@wordsforthewise this is more of an issue if you also want to get other things about the file (modification time, type of file, e.g.) -- then you might as well get it all from a single system call via
os.stat
. Then the difference could run into a substantial number of microseconds :-)– greggoCommented Dec 21, 2019 at 18:24 -
Another advantage of directly using
os.stat()
is, that it accepts filenames relative to a directory file descriptordir_fd
as inos.stat(relname, dir_fd=mydirfd).st_size
, whileos.path.getsize()
does not. When parsing through directory trees,dir_fd
can be a large advantage. Commented Nov 6, 2023 at 19:07
You need the st_size
property of the object returned by os.stat
. You can get it by either using pathlib
(Python 3.4+):
>>> from pathlib import Path
>>> Path('somefile.txt').stat()
os.stat_result(st_mode=33188, st_ino=6419862, st_dev=16777220, st_nlink=1, st_uid=501, st_gid=20, st_size=1564, st_atime=1584299303, st_mtime=1584299400, st_ctime=1584299400)
>>> Path('somefile.txt').stat().st_size
1564
or using os.stat
:
>>> import os
>>> os.stat('somefile.txt')
os.stat_result(st_mode=33188, st_ino=6419862, st_dev=16777220, st_nlink=1, st_uid=501, st_gid=20, st_size=1564, st_atime=1584299303, st_mtime=1584299400, st_ctime=1584299400)
>>> os.stat('somefile.txt').st_size
1564
Output is in bytes.
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3@josch - yes, this is nice, for the "size on disk" you can multiply
stat_result.st_blocks
by the block size, but I'm still searching how to get it programmatically and cross-platform (not viatune2fs
etc.) Commented Apr 22, 2016 at 20:56 -
2@TomaszGandor now
st_blocks
is defined as "Number of 512-byte blocks allocated for file", so you don't have to get the block size. Commented Apr 14, 2023 at 8:45
The other answers work for real files, but if you need something that works for "file-like objects" (e.g. a StringIO
), try this:
# f is a file-like object.
old_file_position = f.tell()
size = f.seek(0, os.SEEK_END)
f.seek(old_file_position)
Caveat #1:
The "file-like object" API isn't a rigorous interface but the API documentation suggests that file-like objects should support seek()
and tell()
, but you should verify this yourself for whatever class you're using.
Caveat #2:
This assumes that the current file position is at the beginning of the file. E.g. if you had already read N bytes from an M-byte file, then this technique would report the size as (M-N). If you don't care about file position at all, you could simplify the 3 lines above to just size = f.seek(0, os.SEEK_END)
.
Caveat #3:
One important difference between this and os.stat()
is that you can stat()
a file even if you don't have permission to read it. Obviously the seek()
approach won't work unless you have read permission.
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2And for the last line, if
os
isn't used:f.seek(old_file_position, 0)
Commented Dec 2, 2015 at 15:11 -
71If you use integer literals instead of named variables, you are torturing anybody that has to maintain your code. There's no compelling reason not to import
os
. Commented Dec 2, 2015 at 16:25 -
5Apparently this is at least a little risky, depending on how Python implements
#seek()
: wiki.sei.cmu.edu/confluence/display/c/… Commented Aug 17, 2018 at 20:35 -
1
f.seek(0, os.SEEK_END)
returns the number of bytes advanced to EOF. Wouldn't this be the same value returned withf.tell()
? Commented Dec 23, 2024 at 18:16 -
1Great point @ErikAnderson. I cleaned up my answer to take advantage of that fact. Commented Jan 2 at 18:07
import os
def convert_bytes(num):
"""
this function will convert bytes to MB.... GB... etc
"""
for x in ['bytes', 'KB', 'MB', 'GB', 'TB']:
if num < 1024.0:
return "%3.1f %s" % (num, x)
num /= 1024.0
def file_size(file_path):
"""
this function will return the file size
"""
if os.path.isfile(file_path):
file_info = os.stat(file_path)
return convert_bytes(file_info.st_size)
# Lets check the file size of MS Paint exe
# or you can use any file path
file_path = r"C:\Windows\System32\mspaint.exe"
print file_size(file_path)
Result:
6.1 MB
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5Line 10 can be changed to
return f'{num:.1f} {x}'
in Python >= 3.5. Commented Jun 7, 2018 at 23:40 -
thank you Matt M., slight update, line 10 can be changed to
return f'{num}{unit}' if unit == 'bytes' else f'{num:.1f}{unit}'
in Python >= 3.5– MZACommented Aug 3, 2020 at 15:05 -
Using pathlib
(added in Python 3.4 or a backport available on PyPI):
from pathlib import Path
file = Path() / 'doc.txt' # or Path('./doc.txt')
size = file.stat().st_size
This is really only an interface around os.stat
, but using pathlib
provides an easy way to access other file related operations.
There is a bitshift
trick I use if I want to to convert from bytes
to any other unit. If you do a right shift by 10
you basically shift it by an order (multiple).
Example:
5GB are 5368709120 bytes
print (5368709120 >> 10) # 5242880 kilobytes (kB)
print (5368709120 >> 20 ) # 5120 megabytes (MB)
print (5368709120 >> 30 ) # 5 gigabytes (GB)
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16This doesn't answer the question. The question is about finding the size of a file, not about formatting the result for human consumption. Commented Apr 9, 2018 at 12:44
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2These numbers are wrong and thus confusing. 5GB is 5e9 bytes. Is this supposed to be some sort of human-readable approximation? Where would you even use something like this?– DreCommented Aug 14, 2018 at 0:29
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41-bit=>2 ... 2-bits=>4 ... 3-bits=>8 ... 4-bits=>16 ... 5-bits=>32 ... 6-bits=>64 ... 7-bits=>128 ... 8-bits=>256 ... 9-bits=>512 ... 10-bits=>1024 ... 1024 bytes is 1kB ... => 20-bits => 1024 * 1024 = 1,048,576bytes, which is 1024kB, and 1MB... => 30-bits => 1024 * 1024 * 1024 = 1,073,741,824 bytes, which is 1,048,576 kB, and 1024MB, and 1GB … You have confused scientific notation and decimal places with the binary/base-2 representation used in computing. 5x9 = 5 x 10^9 = 5,000,000,000 Commented Sep 12, 2018 at 15:33
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7Guys, he hasn't confused anything... he's just given an approximation, which is evident when he says "basically". 2^10 is approx. 10^3. In fact, this approximation is so common that it has a name: Mebi, Gibi, and Tebi are Mega, Giga, and Tera, respectively. Regarding not answering the question, @WillManley , you have a fair point there! ;-p Commented Oct 2, 2018 at 23:36
we have two options Both include importing os module
1)
import os
os.stat("/path/to/file").st_size
as os.stat()
function returns an object which contains so many headers including file created time and last modified time etc.. among them st_size
gives the exact size of the file.
File path can be either absolute or relative.
2) In this, we have to provide the exact file path, File path can be either relative or absolute.
import os
os.path.getsize("path of file")
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1
Strictly sticking to the question, the Python code (+ pseudo-code) would be:
import os
file_path = r"<path to your file>"
if os.stat(file_path).st_size > 0:
<send an email to somebody>
else:
<continue to other things>
You can use the stat()
method from the os
module. You can provide it with a path in the form of a string, bytes or even a PathLike object. It works with file descriptors as well.
import os
res = os.stat(filename)
res.st_size # this variable contains the size of the file in bytes
Here's another self-explanatory example. With this, bytes will be converted into MBs, GBs, or TBs automatically.
from pathlib import Path
from psutil._common import bytes2human
def get_readable_filesize(text_file: Path):
return bytes2human(text_file.stat().st_size)
if __name__ == '__main__':
current_file = Path(__file__).parent.resolve()
print(get_readable_filesize(current_file / 'file.txt'))
#Get file size , print it , process it...
#Os.stat will provide the file size in (.st_size) property.
#The file size will be shown in bytes.
import os
fsize=os.stat('filepath')
print('size:' + fsize.st_size.__str__())
#check if the file size is less than 10 MB
if fsize.st_size < 10000000:
process it ....