Storbinary() Method Of FTP Class In Python

Method Name:


Method Signature:

storbinary(cmd, fp, blocksize, callback, rest)


cmd – The FTP command to be used.

fp – The file object. Typically obtained through the built-in function open().

blocksize - The maximum size of the to be read and sent through the network. The default size is 8192 bytes.

callback- The callback function. If provided, this function is called for every blocksize bytes sent.

rest – The location in the file from which the upload has to be continued.

Return Type:

A success message “226 Transfer complete“ or a failure message like “553 Could not create file”.


  • The method storbinary() initiates a file transfer from an FTP client to a an FTP server using the FTP command STOR.
  • The file transfer is done in binary mode. The method internally sends a “TYPE I” command to the FTP server, before sending a STOR command, meaning the next transfer is a binary image.
  • In binary mode, no translation of CR LF characters is done. This mode of transfer is preferred for binary files. To transfer text files, storlines() method can be used.


# Example Python program to upload a file to an FTP server

# in binary mode

from ftplib import FTP


# Create an FTP object and connect to the server

# as anonymous user

ftpObject = FTP(host="anftpserverhost");



# Login to the server

ftpResponseMessage = ftpObject.login();



# Change to the required working directory

ftpResponseMessage = ftpObject.cwd("/upload");




# Open the file in binary mode

fileObject = open("", "rb");

file2BeSavedAs = ""


ftpCommand = "STOR %s"%file2BeSavedAs;


# Transfer the file in binary mode

ftpResponseMessage = ftpObject.storbinary(ftpCommand, fp=fileObject);




220 (vsFTPd 3.0.3)

230 Login successful.

250 Directory successfully changed.

226 Transfer complete.

Copyright 2023 ©