# Modify an Amazon EBS volume using Elastic Volumes operations
With Amazon EBS Elastic Volumes, you can increase the volume size, change the volume type, or adjust the performance of your EBS volumes. If your instance supports Elastic Volumes, you can do so without detaching the volume or restarting the instance. This enables you to continue using your application while the changes take effect.
There is no charge to modify the configuration of a volume. You are charged for the new volume configuration after volume modification starts. For more information, see the [Amazon EBS Pricing](https://aws.amazon.com/ebs/pricing/) page.
**Topics**
+ [Considerations](#elastic-volumes-considerations)
+ [Limitations](#elastic-volumes-limitations)
+ [Requirements for Amazon EBS volume modifications](modify-volume-requirements.md)
+ [Request Amazon EBS volume modifications](requesting-ebs-volume-modifications.md)
+ [Monitor the progress of Amazon EBS volume modifications](monitoring-volume-modifications.md)
+ [Extend the file system after resizing an Amazon EBS volume](recognize-expanded-volume-linux.md)
## Considerations
+ After you initiate a volume modification, you must wait for that modification to reach the `completed` state before you can initiate another modification for the same volume. You can modify a volume up to four times within a rolling 24-hour period, as long as the volume is in the `in-use` or `available` state, and all previous modifications for that volume are `completed`. If you exceed this limit, you get an error message that indicates when you can perform your next modification.
+ Volume modifications are performed on a best-effort basis, and they can take from a few minutes to a few hours to complete, depending on the requested volume configuration. Typically, A 1-TiB volume can take up to six hours to be modified. However, the time does not always scale linearly with the volume size - a larger volume might take less time, and a smaller volume might take more time.
+ Size increases take effect once the volume modification reaches the `optimizing` state, which usually takes a few seconds.
+ Modification time is increased for volumes that are not fully initialized. For more information see [Manually initialize the volumes after creation](initalize-volume.md#ebs-initialize).
+ If you change the volume type from `gp2` to `gp3`, and you do not specify IOPS or throughput performance, Amazon EBS automatically provisions either equivalent performance to that of the source `gp2` volume, or the baseline `gp3` performance, whichever is higher.
For example, if you modify a 500 GiB `gp2` volume with 250 MiB/s throughput and 1500 IOPS to `gp3` without specifying IOPS or throughput performance, Amazon EBS automatically provisions the `gp3` volume with 3000 IOPS (baseline `gp3` IOPS) and 250 MiB/s (to match the source `gp2` volume throughput).
+ If you encounter an error message while attempting to modify an EBS volume, or if you are modifying an EBS volume attached to a previous-generation instance type, take one of the following steps:
+ For a non-root volume, detach the volume from the instance, apply the modifications, and then re-attach the volume.
+ For a root volume, stop the instance, apply the modifications, and then restart the instance.
## Limitations
+ You can't cancel a volume modification request after it has been submitted.
+ You must increase the volume size. You can't decrease the volume size. However, you can create a smaller volume and then migrate your data to it using an application-level tool such as **rsync** (Linux instances) or **robocopy** (Windows instances).
+ There are limits to the maximum aggregated storage that can be requested across volume modifications. For more information, see [Amazon EBS service quotas](https://docs.aws.amazon.com/general/latest/gr/ebs-service.html#limits_ebs) in the *Amazon Web Services General Reference*.
+ The new volume size can't exceed the supported capacity of its file system and partitioning scheme. For more information, see [Amazon EBS volume constraints](volume_constraints.md).
+ If you are not changing the volume type, then volume size and performance modifications must be within the limits of the current volume type. If you are changing the volume type, then volume size and performance modifications must be within the limits of the target volume type. For more information, see [Amazon EBS volume types](ebs-volume-types.md)
+ [ Nitro-based instances](https://docs.aws.amazon.com/ec2/latest/instancetypes/ec2-nitro-instances.html) support volumes provisioned with up to 256,000 IOPS. Other instance types can be attached to volumes provisioned with up to 64,000 IOPS, but can achieve up to 32,000 IOPS.
+ You can't modify the volume type for Multi-Attach enabled `io2` volumes.
+ You can't modify the volume type, size, or Provisioned IOPS of Multi-Attach enabled `io1` volumes.
+ A root volume of type `io1`, `io2`, `gp2`, `gp3`, or `standard` can't be modified to an `st1` or `sc1` volume, even if it is detached from the instance.
+ If the volume was attached before November 3, 2016 23:40 UTC, you must initialize Elastic Volumes support. For more information, see [Initializing Elastic Volumes Support](requesting-ebs-volume-modifications.md#initialize-modification-support).
+ While `m3.medium` instances fully support volume modification, `m3.large`, `m3.xlarge`, and `m3.2xlarge` instances might not support all volume modification features.