How to Convert VMDK to VHDX (VMware to Hyper-V)?

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In an environment where different versions of the hypervisor are used, it is often necessary to convert virtual machine files from one format to another. In this article, we will look at how to convert a VMware virtual machine’s VMDK file to Hyper-V (VHDX) format.

What are VMDK and VHD/VHDX Virtual Disk Files?

The VMDK format (abbreviation for Virtual Machine Disk) is used to store virtual hard disk images in the VMware ESXi/Workstation/Player/Fusion environment. A VMware virtual disk consists of one or more files (in some cases) with the *.vmdk. extension.

Hyper-V VHD and VHDX Formats

The Microsoft Hyper-V hypervisor uses its own Virtual Hard Drive (VHD) format. Windows Server 2012 Hyper-V introduced a new virtual disk format called VHDX (Virtual Hard Disk v2), which removed many of the limitations of the older VHD format. VHDX supports larger virtual disks, improved resiliency against corruption, metadata protection, and better performance on modern storage systems. The VHDX format is the most commonly used virtual disk format in modern Hyper-V environments.

Why You Need to Convert VMDK to VHDX

In general, virtual disk files from different hypervisors are not directly compatible with each other. In order to run a virtual machine created in the VMware environment on a Hyper-V host, you need to convert the virtual disk file from VMDK to VHDX format.

Neither Hyper-V nor VMware provides a simple built-in standalone tool for directly converting VMDK files to VHDX format. Therefore, you must use V2V migration tools (such as System Center Virtual Machine Manager, VMM), or third-party tools to convert the virtual image files.

In case you are performing large-scale enterprise migrations in Microsoft environment, System Center 2025 – Virtual Machine Manager (VMM 2025) provides you with an enterprise V2V migration workflow for VMware-to-Hyper-V conversions.

Windows Admin Center VM Conversion Extension

Microsoft provides the VM Conversion extension for Windows Admin Center for VMware-to-Hyper-V migrations. Unlike disk-only conversion tools such as qemu-img, the extension migrates the VM itself, including its virtual disks and VM config.

The extension connects to VMware vCenter and uses an initial sync followed by Change Block Tracking (CBT) to replicate changed blocks before the final cutover. During migration, the source VM is powered off for the final sync and the VM is imported into Hyper-V. This can significantly reduce the final downtime compared with a full offline disk copy.

The extension supports multi-disk VMs, static IP config, UEFI/Secure Boot config, and batch migration of up to 10 VMs. It also automatically determines the source boot type: BIOS VMs are migrated to Hyper-V Generation 1, while UEFI VMs are migrated to Generation 2.

The VM Conversion extension is currently in Preview, so production use should be evaluated against the current Microsoft support status and documented limitations. It requires Windows Admin Center Gateway 2410 (build 2.4.12.10) or later, VMware PowerCLI, and VMware VDDK 8.0.3

Things to Do Before Conversion

Before you begin:

• If the source virtual machine is stored in OVF format in VMware datastore, first export the OVF template using the vSphere Client. Then you can download *.OVF file and extract the *.VMDK disk image file from it using 7-Zip;
• We recommend uninstalling VMware Tools either before migration/immediately after the first successful boot in Hyper-V. In some environments, in case you’ll keep VMware Tools installed during initial boot, you may help preserve temporary driver compatibility until Hyper-V integration components are configured;
• You should shut down the VM before conversion. In case the VMware VM contains snapshots, you need to consolidate/remove snapshots before conversion whenever possible. Note that converting snapshot-based VMDK chains may cause inconsistencies/conversion failures.
• Make sure that you have enough free space on your hard disk to save new VHDX file;
• We strongly recommend you to create a backup/clone of the original VM before starting the conversion process.

Azure Migrate is another option for enterprise VMware migration when the target environment is Microsoft Azure rather than an on-premises Hyper-V host. It provides discovery, assessment, replication, and migration workflows for VMware VMs, but it is not a general-purpose VMDK-to-VHDX converter.

Performance and Downtime Considerations. VMDK-to-VHDX conversion is storage-intensive and can take from tens of minutes to several hours for large disks, depending on disk size, storage performance, network throughput, and concurrent workloads. For production environments, you should schedule conversions during low-activity periods/use storage QoS controls where available. For minimal downtime, consider SCVMM/Windows Admin Center VM Conversion Extension, which support migration workflows with a controlled final cutover.

Method 1: Convert VMDK to VHDX with StarWind V2V Converter

You can use the free third-party graphical utility StarWind V2V Converter 9.0.1.848 (current release at the time of writing) to convert between different types of virtual disks.

Download and Install StarWind Converter

Visit the official website to download the tool (to receive the download link, a free registration is required). Run the installer to install the tool on your computer.

Security note. In enterprise environments, you should download third-party utilities only from the vendor’s official website or an approved software repository. Before running the installer, don’t forget to check its Authenticode signature and, when the vendor publishes a checksum, compare the file hash with the vendor-provided value.

StarWind Converter allows you to remotely connect to VMware ESXi and perform an online conversion of a virtual machine and immediately import it to a Hyper-V server.

Select the Remote VMware ESXi Server or vCenter option.

Convert Local VMDK File to VHDX

You can also convert a local VMDK file (for example, a file of a VMware Workstation/Player virtual machine) to VHDX format. To do this, select Local file > specify the source VMDK file and select destination image format VHD/VHDX (Microsoft Virtual Hard Drive).

Specify the destination file path.

Now you can attach the resulting VHDX disk to the Hyper-V virtual machine.

If you need to convert between VMDK and VHDX formats on a regular basis, it is better to do it with the command line tools.

Method 2: Convert VMDK to VHDX Using Qemu-img

In order to convert virtual disk images between different formats, you can use a currently supported QEMU release and verify the installed version with:

qemu-img.exe --version

Install Qemu-img on Linux or Windows

The utility is available for both Linux ($ sudo apt install qemu-utils) and Windows platforms (https://cloudbase.it/qemu-img-windows/). You can list the virtual disk image formats supported by qemu-img.

On Linux, use grep:

qemu-img -h | grep "Supported formats"

On Windows, use findstr:

qemu-img.exe -h | findstr "Supported formats"

Conversion Command Examples

Use the following command to convert a disk image from VMDK to VHDX on Linux:

$ qemu-img convert -p -f vmdk /data/sourceimg.vmdk -O vhdx -o subformat=dynamic /data/outputimg.vhdx

The command to convert a VMDK file in Windows looks like this:

qemu-img.exe convert -p -f vmdk source.vmdk -O vhdx -o subformat=dynamic output.vhdx

After conversion, you should check the resulting VHDX before attaching it to a Hyper-V VM:

qemu-img.exe info output.vhdx
qemu-img.exe check output.vhdx
Get-VHD -Path .\output.vhdx

The subformat=dynamic option creates a dynamically expanding VHDX that initially uses less physical storage. For production workloads, you can also create a fixed-size VHDX:

qemu-img.exe convert -p -f vmdk source.vmdk -O vhdx -o subformat=fixed output.vhdx

Dynamic disks grow as needed, while fixed disks allocate the full size upfront and provide more predictable storage performance.

Validate the VHDX After Conversion

In order to verify the converted VHDX, you can use QEMU and the native Hyper-V PowerShell cmdlets:

qemu-img.exe info output.vhdx
Test-VHD -Path .\output.vhdx

After migrating a VM from VMware to Hyper-V, Windows detects significant virtual hardware changes. In some environments, this can affect Windows activation/app licensing. You need to verify the activation status after the first successful boot and confirm that the VM still complies with your organization’s licensing model.

For volume-licensed Windows deployments, you should verify that the migrated VM can still activate through your organization’s KMS infrastructure or other configured activation service. MAK-activated systems may require additional activation depending on the licensing config and the extent of the hardware changes.

You can check the current activation status with the commands:

slmgr /xpr
slmgr /dlv

For enterprise migrations, you need to include activation verification in the post-migration validation checklist rather than assuming that the existing activation state will always be preserved.

Attach an Existing VHDX Disk to Hyper-V VM

Finally, you can attach the converted VHDX disk to the Hyper-V virtual machine.

1. Open the Hyper-V Manager console;
2. Select New > Virtual Machine;
3. Specify a name and location for the virtual machine files;
4. Select VM generation (Generation 2 is recommended). Keep in mind that some older guest OSs converted from VMware may not boot correctly (as Generation 2 Hyper-V VMs because of UEFI/Secure Boot requirements). In such cases, you may need to create a Generation 1 VM instead;

   

5. Specify the RAM size for the VM;
6. Select Use an existing virtual hard disk item and locate the VHDX file that you received in the previous steps;

   

7. Power on your VM.

Common Boot Problems After VMDK to VHDX Conversion

After you converted a VMware VMDK disk to Hyper-V VHDX, you may encounter situations where VMs fail to boot. This can happen due to:

• Missing storage controller drivers;
• BIOS vs UEFI differences;
• Secure Boot incompatibility;
• Different virtual storage controller types (IDE/SCSI/LSI Logic)
• Legacy VMware drivers.

In case the VM fails to start, you should try:

• Disable Secure Boot temporarily (in Hyper-V VM go to Settings > Security);
• Verify the selected VM generation;
• Boot into recovery mode;
• Remove obsolete VMware Tools components;
• Check if the required Hyper-V Integration Services and drivers are available and up to date.

Keep in mind that Linux guest OSs may additionally require initramfs regeneration, fstab verification, or network interface reconfiguration after migration to Hyper-V.

Wrapping up

It’s a common task for admins during VMware-to-Hyper-V migrations when you need to convert VMware VMDK disks to Hyper-V VHDX format. In case you need one-time migration, we recommend you to use graphical tools (such as StarWind V2V Converter). In case you are looking for a solution that suits better for automation and enterprise workflows, we recommend you to use command-line tools (like qemu-img).

Before performing production migrations, you should always validate:

• VM generation compatibility;
• Secure Boot settings;
• Storage controller support;
• Snapshot consolidation status;
• Backup availability.

After conversion, you may need to additionally reconfig guest OS because of virtual hardware differences between VMware and Hyper-V environments.