Upgrading from Joomla 3.10 to Joomla 4 — a practical, worry-free checklist for beginners

Quick answer: is an automatic upgrade safe?

Quick answer: risk summary and one-line plan

In short: an automatic upgrade can be safe, but only when the server environment, Joomla core, template and all third-party extensions are compatible with Joomla 4. For many sites—especially those with custom or abandoned extensions—the safest route is to prepare first and run the automatic upgrade on a staging site, not on production.

One-line plan: Audit → Clone to staging → Backup → Upgrade on staging → Test → Upgrade production.

Practical example

Example one-line procedure to follow now: export an extension list from Extensions > Manage, check compatibility for each extension, create a staging copy with the same PHP version, take a verified backup, run the Joomla Update on staging and test the most-used pages, and then upgrade production during a maintenance window.

Warnings

• Do not run the automatic upgrade on production without a verified backup and a successful staging run.
• Administrator warnings about extensions are indicators of potential problems, not guarantees. Investigate every warning before proceeding.

Joomla 4 upgrade prerequisites (system requirements and PHP)

Before attempting any migration, confirm the server environment meets Joomla 4 requirements, and that your Joomla 3.10 installation is fully updated.

Confirm Joomla 3.10 is fully updated

• Make sure your Joomla 3.10 installation is updated to the latest 3.10.x release available.
• Apply extension updates that are explicitly for Joomla 3.10 before migrating.

Check PHP, database and server compatibility

Joomla 4 requires a newer PHP version and certain database versions and PHP extensions. To check your environment:

1. Open System > System Information in the Joomla administrator to view current PHP, MySQL/MariaDB, and loaded PHP extensions.
2. Or place a simple phpinfo() file on a staging server to inspect PHP settings (only on staging; remove it afterwards).
3. Verify required PHP extensions such as mbstring, json, xml, zip, and others are present.

Warning: changing the server PHP version on production without testing can break other sites hosted on the same account. Always replicate the environment in staging first.

Verify exact minimum PHP and database versions and required PHP extensions against the official Joomla documentation before making production changes.

Pre-upgrade checklist — what to do before you touch the live site

Do these preparatory steps before touching production. This section provides a copy-paste checklist you can follow.

Ready-to-use pre-upgrade checklist

1. Take a full site backup (files and database). Do not skip this.
2. Export or record a list of installed extensions (components, modules, plugins, templates, libraries) and their versions.
3. Make sure Joomla 3.10 core is updated to the latest 3.10.x release.
4. Update extensions that clearly state support for the latest Joomla 3.10 release.
5. Create a staging copy that mirrors production (files, DB and PHP version).
6. Disable caches, put site(s) into maintenance mode if your backup or cloning method requires it.

Backup verification and safety steps

• Always test-restore a backup to a staging or local environment to confirm it can be restored.
• Keep at least one off-site copy of backups and several restore points if possible.

Warning: never assume a backup is usable. Test the restore before relying on it for rollback.

Audit installed extensions, plugins and templates

Third-party extensions and templates are the most common causes of upgrade problems. A systematic audit reduces surprises.

List installed extensions and check vendor support

1. From Extensions > Manage, export or copy the extension list. If your admin lacks an export function, copy the list into a spreadsheet manually.
2. Add columns for: extension name, type, installed version, vendor/developer, Joomla 4 compatibility status, action required.

How to find extension compatibility info (developer site, JED)

Check the Joomla Extensions Directory (JED), extension vendor websites, GitHub repositories and changelogs for Joomla 4 compatibility notes. If the vendor mentions an upcoming Joomla 4 update, note the planned release date and any migration instructions.

Disable non-essential extensions for testing

On your staging site, temporarily disable optional plugins and modules to narrow down problems. Always record what you change so you can revert after testing.

Practical example audit workflow

Example spreadsheet rows may look like:

• "Akeeba Backup — Component — 9.5.0 — Vendor X — OK — No action"
• "Custom contact component — Component — 1.2.3 — Unknown — Abandoned — Replace or hire developer"

Warning: do not ignore extensions marked as abandoned; they commonly block upgrades. Even extensions that claim compatibility may still require testing on staging.

Handling custom or abandoned extensions

If an extension appears abandoned or is custom-built, you have several options. The correct choice depends on how critical the extension is to site functionality.

Options for abandoned/custom components (update, replace, disable)

• Contact the vendor or developer to ask about Joomla 4 support.
• Search for maintained forks or replacements on JED or GitHub.
• If no update exists, consider replacing the extension with a maintained alternative and plan data migration if needed.
• As a last resort, hire a developer to port the extension to Joomla 4.

Sample decision flow for abandoned custom extensions

1. Contact vendor/support.
2. If vendor unavailable, search for forks or alternatives.
3. If a compatible replacement exists, plan migration and test data mapping on staging.
4. If no replacement, isolate the extension on staging and test site functionality without it; if critical, hire a developer to port it.

Practical example: if a custom contact component is only used on one form, replacing it with a modern contact extension and mapping stored messages may be faster than porting the old code.

Warning: directly editing extension files on a live site can create maintenance and security issues. If you must modify code, ensure you have version control and backups.

Create a staging copy and test the upgrade

Staging is the place to find and fix problems safely. A valid staging environment mirrors production for PHP, database, and configuration.

How to clone your site: manual vs backup tool vs host staging

• Manual clone: copy files via FTP/SFTP, export the production database and import into a staging database, and update configuration.php and site URLs.
• Backup tool restore: create a full backup on production (files + DB) and restore to a staging subdomain using the same tool. Popular backup tools exist for Joomla; verify their compatibility with restores to staging.
• Host-managed staging: many hosts offer one-click staging in their control panels. Confirm the staging site uses the same PHP and database versions or allows you to match them.

How to use backups to restore (example tools)

Akeeba Backup is commonly used for Joomla sites to create full-site archives and restore them on staging. If you use a backup tool, follow its restore instructions and verify the site functions on staging.

Practical example

Example steps using a backup tool: run backup on production, download the archive, upload and extract on staging, import the installer script if required, and run the restore. After restoring, verify site URL and database settings and block search engines from indexing the staging site.

Warning: if staging does not match production PHP or DB versions, issues may be hidden or new problems introduced. Keep staging as close as possible to production.

Backup and rollback strategy

A clear rollback plan gives you confidence to upgrade. Follow a documented backup and restore process and test it on staging.

How to use backups to restore (example tools)

Example workflow with a backup tool:

1. Create a full backup on production immediately before the planned upgrade.
2. Download and store the archive off-site (local drive or cloud storage).
3. Test the archive by restoring it to a staging server.

Rollback checklist

1. Confirm backup integrity and archive location.
2. Put the site in maintenance mode to prevent new content during restore.
3. Restore files and database from the backup archive.
4. Clear caches and verify front-end and admin functionality.
5. Remove maintenance mode once verified.

Warning: restoring a backup will revert any content changes made after the backup. For high-traffic or content-updated sites, schedule a content freeze window during the upgrade.

Step-by-step upgrade on staging (then production)

Run the upgrade first on staging and only repeat it on production when staging passes all checks.

Step-by-step: perform the upgrade in the Joomla Update component

1. On staging, verify that Joomla 3.10 is fully updated and that all pre-upgrade checks are complete.
2. Open Components > Joomla Update (or Extensions > Update depending on your admin layout).
3. Switch update channels if required and choose the Joomla 4 upgrade option according to official guidance. Verify the exact steps against the official Joomla documentation before proceeding.
4. Run the update and monitor progress. Allow time for database migrations and post-update scripts to execute.
5. After the update completes, clear Joomla caches and browser caches, then inspect the site for errors.

Verifying frontend and backend after upgrade

• Log into the administrator and check Extensions > Manage for any disabled or broken extensions.
• Visit critical front-end pages, submit forms, and test user login and any e-commerce flows if present.
• Inspect PHP error logs and Joomla logs for warnings or fatal errors.

Warning: long-running updates may hit PHP execution limits. If the update fails due to timeouts, do not retry on production—restore the backup and investigate on staging. Consider running command-line updates if recommended by Joomla docs and your host supports it.

Post-upgrade checks and common fixes

After a successful upgrade, perform a focused set of checks to catch common issues quickly.

Verifying frontend and backend after upgrade

1. Check the homepage and top-level navigation.
2. Open category listings, articles, and key components (contact forms, events, shop pages).
3. Login to the administrator and visit extension management pages for each third-party extension.

Common post-upgrade issues (template, menu, login, admin errors)

• Templates may require updates to be Joomla 4 compatible; module positions or overrides can break layouts.
• Third-party extensions might need updated versions or reinstallation.
• Custom code or overrides may cause PHP errors; check the logs to isolate files involved.

When to roll back and how to troubleshoot logs

If a critical feature is broken and no quick fix is available, roll back using your verified backup. Collect error messages, PHP traces and relevant Joomla logs, and document the steps you took before consulting a developer.

Warning: some post-upgrade fixes (template conversions, deep extension porting) require developer skills. Avoid editing core files—use overrides or updated extensions instead.

When to get professional help

There are good moments to call in a Joomla professional. If you meet any of the following criteria, engage a developer or a trusted Joomla agency:

• Critical functionality depends on custom or abandoned extensions.
• The site serves revenue-critical traffic and downtime must be minimized.
• Post-upgrade errors are complex PHP or database issues beyond basic debugging.

Hiring a developer: what information to provide

Prepare a clear brief to speed up troubleshooting:

• Staging URL and production URL.
• Joomla and PHP versions used on staging and production.
• Extension list with versions and notes about abandoned/custom items.
• Backups (archive ID) and error log extracts with timestamps.
• Exact steps you tried and where the process failed.

When to choose a migration vs a compatibility fix

If a vendor is not maintaining an extension and no modern replacement exists, plan for a migration or a custom port. For templates, consider switching to or purchasing a Joomla 4-ready template if conversion is costly.

Warning: choose developers with proven Joomla 3-to-4 migration experience and require version control and backups before code changes.

Resources and next steps

Final recommended steps and authoritative resources to consult before performing any production upgrade.

Useful references and tools

• Official Joomla documentation — check the migration and system requirements pages before upgrading.
• Joomla Extensions Directory (JED) — for checking extension compatibility and vendor information.
• Backup tools and hosting staging features — choose tools compatible with your workflow and verify restore procedures.

Next steps checklist

1. Finish the extension audit spreadsheet and classify each item.
2. Create a staging copy that mirrors production and set the same PHP and DB versions.
3. Take and verify a full backup and test restore on staging.
4. Run the Joomla upgrade on staging, test thoroughly, and document issues and fixes.
5. Schedule a production upgrade during a low-traffic window with a content freeze if needed.

FAQ

Will my site break if I attempt an automatic upgrade?

Not necessarily, but it depends on server requirements and third-party extensions. Always audit extensions, create a staging copy, and have a verified backup before attempting the upgrade on production.

How do I identify which extensions, plugins or templates are incompatible with Joomla 4?

Export the list of installed extensions and check each entry on the Joomla Extensions Directory and vendor changelogs for Joomla 4 compatibility. On staging, disable non-essential extensions to see whether the site runs without them.

What environment and PHP versions are required before upgrading?

Joomla 4 requires a newer PHP version and specific database versions and PHP extensions. Verify the exact versions and requirements on the official Joomla requirements page before changing environments.

How do I create a safe staging copy of my live site for testing?

Options include manual cloning (files + DB), restoring a backup archive to a staging subdomain using a backup tool, or using host-managed one-click staging. Ensure staging matches production PHP and database versions and block it from search engines.

Which backups and rollback steps should I take before upgrading?

Take a full backup (files + DB), verify the backup by restoring it to staging, store an off-site copy, and prepare a tested rollback checklist so you can restore production quickly if needed.

What should I do with custom or abandoned (ghosted) extensions?

Search for vendor updates or forks, consider replacement extensions, isolate or disable the extension on staging to test impact, and hire a developer to port critical custom extensions if necessary.

How do I apply the upgrade step-by-step in Joomla 3.10 and verify success?

On staging: update Joomla 3.10 to the latest 3.10.x, follow the Joomla Update component steps to move to Joomla 4 (verify the exact procedure in official docs), run the update, clear caches and test front-end and admin features. Repeat on production with backups in place when staging passes.

When should I call a developer or migrate to a new extension?

Call a developer when the site uses complex custom code, critical functionality fails after testing, or the extension is abandoned and no reliable replacement exists. Provide logs, backups and a concise brief to speed up help.

Conclusion

Upgrading from Joomla 3.10 to Joomla 4 is achievable for site owners and beginners when approached methodically: audit extensions, create a staging copy that matches production, verify backups with a test restore, run the upgrade on staging, and only proceed to production once tests pass. Abandoned or custom extensions present the most common challenges and may require replacement or developer assistance.

Before you act, verify critical technical details such as exact Joomla 4 system requirements and the official upgrade procedure against the Joomla documentation. With careful preparation and a rollback plan you can reduce risk and complete the migration confidently.