---
title: "Resize an instance via Horizon"
description: "Learn how to resize your instance using the OpenStack Horizon interface."
url: https://docs.us.ovhcloud.com/en/public-cloud/compute/resize-of-an-instance
lang: en
---
> For AI agents: the complete documentation index is available at https://docs.us.ovhcloud.com/en/llms.txt, the full documentation bundle is available at https://docs.us.ovhcloud.com/en/llms-full.txt.

# Resize an instance via Horizon

**Learn how to resize your instance using the OpenStack Horizon interface.**

As a result of increased activity, or simply new needs, your instance may not be able to meet this new burden due to a lack of resources. However, with the Public Cloud, you can increase the resources available to your instance, and this can be done with just a few clicks.

**Warning:**

**NOTE:** Only upscaling is possible for classic models. In addition, this manipulation causes the instance to be shut down for the time of the operation.

**Tip:**

Flex instances allow resizing to higher or lower models due to a locked single disk size.

 

## Requirements

- An [OVHcloud Public Cloud instance](https://docs.us.ovhcloud.com/en/public-cloud/compute/getting-started.md)
- [Access to the Horizon interface](https://docs.us.ovhcloud.com/en/public-cloud/cross-functional/introducing-horizon.md)

 

## Instructions

Log into the [Horizon interface](https://horizon.cloud.ovh.us/auth/login/), and make sure you are in the correct region. You can verify this in the top left corner.

Next, click on the `Compute` menu on the left side and select `Instances`. Select `Resize Instance` in the drop-down list for the corresponding instance.

 

### Template Selection Tab (Flavor Choice)

This section shows the current template (old flavor) and allows you to select a new template (new flavor) for the instance resource.

 

#### Flavor Details

In this section, you will see the resources associated with the new template you have chosen.

 

#### Project Limits

Under this section, you can view the occupied resources compared with the total resources allocated to the project.

**Warning:**

**NOTE:** Please note that you cannot switch models when resizing an instance. A resizing can only be done from one Linux model to another Linux model, or from one Windows model to another Windows model.

 

### Advanced Options

Use this section to manage the **Disk Partition** and **Server Group**.

Once the configuration is complete, click on `Resize`.

 

### Resizing a disk in Windows

When performing a resize for a Windows Instance, please note that the partition size is not automatically updated, so you will have to extend it using the **disk manager**:

- Right-click on the `Start` menu and launch the disk manager by clicking on `Disk Management`:

- Right-click on the main partition, then click on `Extend Volume`.

- In the `Extend Volume Wizard` menu, click on `Next` to proceed. In the next tab, choose the disk resources to extend and click on `Next`.

  Once done, click on `Finish` to confirm your choice.

- The new disk size will then be displayed in the disk manager.

 

## Go further

Browse all the [Compute guides](https://docs.us.ovhcloud.com/en/public-cloud/compute/landing-page-compute.md).

Browse the rest of the [OVHcloud US documentation](https://docs.us.ovhcloud.com/en/index.md) for guides on our other products and services.

Learn more about [Public Cloud Compute](https://us.ovhcloud.com/public-cloud/compute/) on the OVHcloud US website.