Record the current environment and intended target
Record the site's WordPress, PHP, plugin and theme versions, required PHP extensions and important scheduled jobs. Choose a target that your host provides and your maintained components support. Check the PHP project's support table and the WordPress PHP compatibility table for the versions you use.
NosHost's queued scanner currently offers targets through PHP 8.4. An offered target describes scanner coverage, not a recommendation to run that version. If your intended version is absent, do not substitute a scan for a different target and call the upgrade checked.
Keep a restorable files-and-database backup, a staging copy and a way to restore the previous PHP configuration. Confirm the rollback process with your host before the live change.
Choose local report analysis or a source scan
PHP Upgrade Readiness Checker has two distinct paths:
- Analyze an existing report in your browser. Import native PHPCompatibility JSON or a supported evidence report. For a direct PHPCS import, provide the actual source site, UTC collection time, scanned target, file count and completed-scan status. Read the evidence collection guide for formats and limits.
- Upload selected source for queued static analysis. This sends the source ZIP to NosHost. The limit is 2 MiB compressed, 8 MiB expanded and 100 PHP files. Select only plugin or theme source you have permission to analyze. Remove configuration, credentials, keys, uploads and private data first; do not upload a site backup.
The scanner uses bundled prerelease compatibility rules and does not execute the source. Review the source-upload and backup retention details before using that path. Local report analysis does not upload the imported report.
Check the evidence before trusting a result
Confirm which component release and files were scanned, the target PHP version, scanner/ruleset and collection time. A scan of one plugin leaves the theme, other plugins, dependencies and custom code untested. The manual WordPress exporter records environment facts; it does not run a PHPCompatibility scan for you.
Missing target, no scanned files, an incomplete scan or unrecognized rules can leave the result unavailable. The analyzer also flags stale evidence. Fix the collection problem or rerun the scan rather than marking an unknown scope complete.
Use each finding to select the next review
The report lists the recorded file, line, compatibility rule and message type. Review the affected source with its maintainer and check whether a supported component release resolves it. Retest the same source scope and target after a change.
A completed scan with no recognized findings means that those static rules reported none in that supplied scope. It cannot establish runtime compatibility, available extensions or a working plugin combination. PHP's 8.3 to 8.4 migration guide is one version-specific example; consult the guides for every version crossed by your own upgrade.
Test the real workflows on staging
Switch the staging environment to the intended PHP version and extensions. Check public pages, login, admin editing, forms, scheduled jobs and integrations you rely on. For WooCommerce, use synthetic customer details and a test gateway to exercise cart, checkout and the resulting background work.
Record each expected and actual result. If a workflow fails, collect a bounded PHP log and follow the fatal-error investigation guide. After repairing it, repeat that workflow and capture fresh evidence. Schedule the live switch only after reviewing these results and your rollback plan. NosHost does not switch PHP versions or apply automatic fixes.
Sources
Reviewed on 6 November 2026. WordPress PHP update guidance, PHP supported versions, WordPress version compatibility and PHP 8.4 migration guide.