WordPress migration plugins compared

Migrating WordPress websites to new hosting doesn’t always go to plan.

Do these challenges sound familiar?

• Trying to back up the source site when storage is limited.
• The connection cuts out mid migration!
• Moving from low-quality hosting and the associated memory limits!
• Migrating a standalone site to a multisite network (or moving a subsite into a new network).
• Large databases and file-heavy sites.

Every hiccup adds extra time and cost. That’s why I decided to put several leading migration plugins to the test under real-world conditions.

After chatting with WordPress colleagues in the hosting space, I decided to test these plugins specifically:

• All-In-One Migration
• Total Upkeep by BoldGrid
• UpdraftPlus
• InstaWP
• BlogVault
• Migrate Guru
• WP Migrate
• Duplicator

They’re actively used by hosts to migrate WordPress websites into new environments. They each boast a rating of at least 4 out of 5 stars on the WordPress plugin directory.

I tested all eight plugins under various real-world conditions, including:

Storage-constrained backups

A common pitfall for WordPress hosting businesses; I tested each plugin’s resolve where storage on the incumbent host was in short supply.

To simulate a constrained storage environment, I created a 2GB sparse bundle disk image. The WordPress site was moved to this disk, and the disk was filled to 99% capacity using dummy files.

Connection cut-outs

Network interruptions were simulated using terminal commands to disable and re-enable the network interface on the server. This created connection drops lasting 10 seconds, repeated three times during the migration to evaluate recovery.

Memory restrictions (migrating from low to high quality hosting)

I simulated a low quality hosting environment with low memory (128MB), a single CPU core, limited storage, and slow disk I/O. Bandwidth and latency were restricted to simulate a low-resource server.

The destination site used a high-resource environment (512MB memory, 4 CPU cores, SSD storage and high bandwidth).

Large databases

I generated a 300MB database then put each plugin through its paces.

The database consisted of around 1,000 posts, comments and users.

In this test, I used the same high-resource environment as the above test (512MB memory, 4 CPU cores, SSD storage and high bandwidth) to ensure the results could be attributed to database size, rather than other resource constraints.

File-heavy sites

I packed the media library full of images and videos to see how it impacted plugin performance. The total file size exceeded 500MB.

Atomic restore

I also tested whether the plugins had atomic restore capabilities.

Atomic restore refers to a restoration process where the entire operation is executed as one single, indivisible unit (all-or-nothing restoration). In other words, the website’s data is migrated completely, or not at all, ensuring that there’s no intermediate state with only part of the data migrated.

I tested whether each plugin supported atomic restoration and if these features functioned correctly.

WordPress multisite networks

Finally, I tested the plugins’ abilities to migrate WordPress multisite networks. I tested two things here:

1. The ability of each plugin to migrate a stand-alone WordPress site into an existing multisite network.
2. The ability of each plugin to migrate an existing subsite into another WordPress multisite network.

First up, a simple migration

First up, I ran a simple migration to benchmark the eight plugins against a standard environment to these technical specs:

• 512MB PHP memory limit
• 4 CPU cores
• 4GB SSD storage
• High bandwidth and low latency connection

I created the environments using Local by Flywheel. For plugins that couldn’t function locally (due to domain resolution issues) I simulated the same configurations using a Cloudways DigitalOcean server.

Here’s how the contenders performed:

Storage-constrained backups

Only four of the eight plugins were successful at migrating a WordPress website when the source site was at 99% storage capacity; BlogVault, InstaWP, UpdraftPlus and Migrate Guru.

Migration plugins that first transfer data to an intermediary server, such as Migrate Guru, InstaWP and BlogVault did well here since the backups don’t have to be stored on the source site’s (storage constrained) server.

The trade-off is that transferring to an intermediary site first is less efficient. The risk of loss and corruption also increases since the transfer is made twice, once to the intermediary and then to the final destination.

UpdraftPlus did well to achieve a successful migration at 99% capacity via the more direct site-to-site method whilst also being faster and more resilient in later tests.

Whilst UpdraftPlus can migrate even at 99% capacity, it draws the line at 100% since it needs enough space left for the largest file on the site, or the largest zip archive*, whichever is larger.

*UpdraftPlus users can split large sites into multiple zip archives to support migration on constrained host environments.

Here’s how each of the eight plugins performed:

Connection cut-outs

Just three of the plugins achieved a successful migration after a connection interruption; UpdraftPlus, BlogVault and Migrate Guru.

UpdraftPlus was able to recover despite a failure mid-migration, continue from where it left off, without user intervention whilst providing clear information to the user as to the status of things.

Memory restrictions (migrating from low to high quality hosting)

I experienced an issue with exporting ‘plugins/mu plugins/other files’ from the source site via Duplicator so I’ve marked this as a partial success.

Every other plugin succeeded. UpdraftPlus, All-In-One WP Migration and Total Upkeep by BoldGrid were the fastest at around 1 minute 40 seconds.

Large databases

WP Migrate was only able to transfer the database. Media, themes, plugins and other files were unsuccessful.

Every other plugin completed the migration successfully but some were notably slower.

UpdraftPlus and BoldGrid both came in at under two minutes, followed by All-in-One and Duplicator at around the 3 minute mark.

InstaWP was the slowest at 14 minutes, 18 seconds.

File heavy sites

WP Migrate struggled to migrate the file heavy sites. Only the database was successfully restored. All the other plugins performed successfully.

UpdraftPlus and BoldGrid both came in at under 2 minutes.

InstaWP and BlogVault came in at around the 5 – 6 minute mark.

Duplicator and Migrate Guru were the slowest to migrate a file heavy site at 8:23 and 9:48 respectively.

WordPress multisite networks

Stand-alone site into a WordPress multisite

Only All-In-One WP Migration, UpdraftPlus and Duplicator were successful.

It’s not clear whether BlogVault is supposed to support migration of a stand-alone site into a multisite network. In my test, the stand-alone site replaced the entire network!

WP Migrate was a fail and the remaining plugins do not support migration of WordPress multisite networks.

Subsite into a different WordPress multisite network

As before, only All-In-One WP Migration, UpdraftPlus and Duplicator were successful.

InstaWP, Migrate Guru and Total UpKeep don’t support migration of WordPress multisite networks.

I couldn’t see an option for migrating a subsite into a multisite network in the BlogVault plugin and it isn’t too clear in the documentation either. I tried anyway. The subsite replaced the network again.

WP Migrate generated the same error message as above (cURL error 42: operation aborted by callback) even after debugging and resetting the environments.

Atomic restore

Last up, I checked whether our eight plugins had an atomic restore feature. Super important, it ensures an ‘all or nothing’ approach to database migration, which avoids a situation where only part of the database is migrated (and the associated issues).

Each plugin has its own strengths and weaknesses.

For example InstaWP, which first migrates to an intermediary server, excels when the source site has memory or storage limitations. Migrate Guru performed well for most migrations, except for WordPress multisite. However, its lack of atomic restore features is a drawback.

Objectively, UpdraftPlus was the most consistent performer, delivering strong results across all categories.