Odoo is open source, you can download it here. By filling this form, you will receive Odoo, all official modules and an installation manual.
To benefit fom the latest features or if you are evaluating Odoo, we advise you to use Odoo online: Start now with Odoo online
Download Odoo with:
The 240 official modules
Auto-installer (for windows/ubuntu)
Start using online for free:
No credit card required. Instant Access. Open Source.