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Easy to use download tool and API for different types of Firefox and Thunderbird builds

PyPI version Build Status Stories in Ready


mozdownload is a python package which handles downloading of Mozilla applications.


If the tool should only be used for downloading applications we propose to install it via pip. The following command will install the latest release:

pip install mozdownload

Otherwise follow the steps below to setup a development environment. It is recommended that virtualenv and virtualenvwrapper be used in conjunction with mozdownload. Start by installing these. Then first fork our repository into your own github account, and run:

git clone
cd mozdownload
python develop

More detailed developer documentation can be found in the wiki.

Command Line Usage

The mozdownload command will download the application based on the provided command line options.


Download the latest official Firefox release for your platform (as long as there is no 64bit build of Firefox for Windows64, users on that platform have to download the 32bit build):

mozdownload --version=latest

Download the latest Firefox Aurora build for Windows (32bit):

mozdownload --type=daily --branch=mozilla-aurora --platform=win32

Download the latest official Thunderbird release for your platform:

mozdownload --application=thunderbird --version=latest

Download the latest Earlybird build for Linux (64bit):

mozdownload --application=thunderbird --type=daily --branch=comm-aurora --platform=linux64

Download this README file:

mozdownload --url=

Download a file from a URL protected with basic authentication:

mozdownload --url= --username=admin --password=password

Run mozdownload --help for detailed information on the command line options.

Command Line Options

To see the full list of command line options, execute the command below and check the list of options for the build type to download:

mozdownload --help


Beside the CLI mozdownload also offers an API to be used. To create specific instances of scrapers the FactoryScraper class can be used. Here some examples:

# Create a release scraper for the German locale of Firefox 40.0.3
from mozdownload import FactoryScraper
scraper = mozdownload.FactoryScraper('release', version='40.0.3', locale='de')

# Create a candidate scraper for Windows 32bit of Firefox 41.0b9
from mozdownload import FactoryScraper
scraper = mozdownload.FactoryScraper('candidate', version='41.0b9', platform='win32')

# Create a daily scraper for the latest Dev Edition build on the current platform
from mozdownload import FactoryScraper
scraper = mozdownload.FactoryScraper('daily', branch='mozilla-aurora')

All those scraper instances allow you to retrieve the url which is used to download the files, and the filename for the local destination:

from mozdownload import FactoryScraper
scraper = mozdownload.FactoryScraper('daily')
print scraper.url
print scraper.filename

To actually download the remote file the download() method has to be called:

from mozdownload import FactoryScraper
scraper = mozdownload.FactoryScraper('daily')
filename =
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