Compare PHP Code Online Free — Side-by-Side Diff With Syntax Highlighting

PHP codebases have long lives. Legacy WordPress plugins, Laravel applications mid-refactor, Symfony services getting updated — sooner or later you have two versions of a PHP file and need to see exactly what changed between them. Line-by-line reading is slow and error-prone on anything longer than a few dozen lines.

The Raven Code Diff viewer handles PHP natively with full syntax highlighting. Paste both versions, select PHP, and the diff highlights every changed function, class definition, variable, and string.

PHP Code Patterns the Diff Viewer Highlights

• Function and method definitions: Signature changes, added/removed parameters, return type changes
• Class and interface changes: Inheritance changes, added properties, visibility modifiers, trait use statements
• Laravel routing and controllers: Route definitions changed, middleware added, controller method signatures
• WordPress hooks and filters: add_action, add_filter calls — what hook name, priority, or callback changed
• SQL queries in PHP: Raw query strings, prepared statement changes, ORM query builder chains
• Composer dependencies referenced in code: Namespace use statements, class instantiation from packages
• Config arrays: PHP config files with nested arrays — see exactly which keys changed
• Template files (Blade, Twig, raw PHP): HTML mixed with PHP logic, loop and condition changes

Sell Custom Apparel — We Handle Printing & Free Shipping

When PHP Code Comparison Saves Real Time

Plugin or package upgrades: When you update a WordPress plugin or Composer package and want to understand what changed before testing, diffing the old and new version is faster than reading a changelog.

Legacy code modernization: Comparing PHP 5.x code to its PHP 8.x rewrite shows every syntax change — short closures, named arguments, null coalescing additions.

Debugging a regression: If a feature broke after a recent edit, comparing the working version from version control against the current file pinpoints the change.

Code review without a GUI client: Paste the two versions of a file you received over email or Slack and review the diff in your browser without needing a Git client or IDE open.

How to Compare PHP Code Online

1. Open the code diff viewer
2. Paste the original PHP code into the left panel
3. Paste the updated version into the right panel
4. Select PHP from the language dropdown for proper syntax coloring of keywords, strings, variables, and HTML mixed content
5. Added lines highlight in green, removed lines in red
6. Adjust the context slider to focus on just the changes or see full file context

No login, no upload, no server. The diff runs entirely in your browser.

Frequently Asked Questions

Can I compare PHP template files with mixed HTML and PHP?

Yes. The PHP syntax highlighter handles files with mixed HTML and PHP content — the highlighting applies to both the PHP blocks and the surrounding markup.

Does it work for comparing Laravel Blade templates?

Yes. Blade templates are PHP files with additional directives. The diff viewer shows all changes including Blade-specific syntax like @if, @foreach, and component syntax.

Can I compare PHP files without uploading them to a server?

Yes. Paste the file contents directly into the diff viewer panels. Nothing is uploaded — all processing happens in your browser.