Released under the terms of the GNU General Public License and, optionally, the CDDL for most files of the source distribution, VirtualBox is free and open-source software, though the Extension Pack is proprietary software, free of charge only to personal users.

[12] VirtualBox was first offered by InnoTek Systemberatung GmbH, a German company based in Weinstadt, under a proprietary software license, making one version of the product available at no cost for personal or evaluation use, subject to the VirtualBox Personal Use and Evaluation License (PUEL).

[13] In January 2007, based on counsel by LiSoG, InnoTek released VirtualBox Open Source Edition (OSE) as free and open-source software, subject to the requirements of the GNU General Public License (GPL), version 2.

[14] InnoTek also contributed to the development of OS/2 and Linux support in virtualization[15] and OS/2 ports[16] of products from Connectix which were later acquired by Microsoft.

A supplementary package, under a proprietary license, adds support for USB 2.0 and 3.0 devices, Remote Desktop Protocol (RDP), disk encryption, NVMe, and Preboot Execution Environment (PXE).

[28] Since VirtualBox version 5.1.30,[29] Oracle defines personal use as installation on a single computer for non-commercial purposes.

The full package was offered gratis under the PUEL, with licenses for other commercial deployment purchasable from Oracle.

A second package called the VirtualBox Open Source Edition (OSE) was released under GPLv2.

The host OS and guest OSs and applications can communicate with each other through a number of mechanisms including a common clipboard and a virtualized network facility.

VirtualBox can also connect to iSCSI targets and to raw partitions on the host, using either as virtual hard disks.

[37] Both ISO images and physical devices connected to the host can be mounted as CD or DVD drives.

By default, VirtualBox provides graphics support through a custom virtual graphics-card that is VBE or UEFI GOP compatible.

By default, VirtualBox uses NAT through which Internet software for end-users such as Firefox or ssh can operate.

In both cases, VirtualBox uses CSAM and PATM to inspect and patch the offending instructions whenever a fault occurs.