Xdebug
What Xdebug is
Xdebug is a PHP extension that adds debugging and analysis features to PHP development. Its step debugger lets developers move through code interactively to inspect control flow and data structures. It improves var_dump() output and adds stack traces for notices, warnings, errors, and exceptions. Function tracing can record calls, arguments, and invocation locations, with optional variable assignments and return values. Its profiler reports execution and memory-use information in Cachegrind-compatible files, while code coverage shows which parts of a codebase execute during PHPUnit tests. Xdebug uses the DBGp protocol, which is supported by nearly every PHP IDE, including Visual Studio Code and PhpStorm. Installation instructions cover Linux, macOS, Windows, and Unix-like systems, with compatibility documented by PHP version. Xdebug is free. Paid Pro costs £200 per year for one developer, and Business costs £1,000 per year for 2–20 developers; both include email technical support. Xdebug Cloud is described as a relay for situations where network or firewall conditions block direct debugger connections.
Who it suits
Xdebug suits PHP developers who need interactive debugging, traces, profiling, or code coverage. Paid support tiers are available for individual developers and teams of 2–20.
What it does well
- Free PHP extension.
- Step debugger supports interactive code inspection.
- Profiler outputs Cachegrind-compatible files.
- DBGp is supported by nearly every PHP IDE.
- Browser helper extensions are listed for major browsers.
What to know first
- Paid Pro costs £200 per year.
- Business costs £1,000 per year.
- Community support has low issue priority.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Business | £ 1000/year * · 2–20 developers · e-mail tech support · high issue priority · one-hour presentation or workshop · opt-in monthly e-mail newsletter · invoice · thank-you link on site | £1,000 a year |
| Pro | £ 200/year * · 1 developer · e-mail tech support · medium issue priority · opt-in monthly e-mail newsletter · invoice | £200 a year |
As xdebug.org lists them, read 2 Oct 2026. The maker's own page has the final word.
Getting started
- Visit the Xdebug website.
- Choose installation instructions for Linux, macOS, Windows, or a Unix-like system.
- Check compatibility information for your PHP version.
- Use a PHP IDE or text-based editor that supports DBGp.
- Configure the debugger connection from Xdebug to your IDE.
Verdict
Xdebug combines step debugging with tracing, profiling, and code coverage for PHP projects. Direct debugger connections may be blocked by network or firewall conditions; Xdebug Cloud is described as a relay for those cases.
Questions
Is Xdebug free?
Xdebug has a free plan. Paid plans start at £200/yr.
What does Pro cost?
Pro costs £200 per year for one developer and includes email technical support with medium issue priority.
What does Business cost?
Business costs £1,000 per year for 2–20 developers. It includes email technical support with high issue priority and a one-hour presentation or workshop.
Which operating systems are covered by installation instructions?
Instructions cover Linux, macOS, Windows, and Unix-like systems. Source builds are described for Unix-like operating systems.
Which PHP IDEs can connect to Xdebug?
Xdebug uses DBGp, supported by nearly every PHP IDE, including Visual Studio Code and PhpStorm, as well as text-based editors.
Does Xdebug support remote debugging and breakpoints?
Yes. The listed capabilities include remote debugging, conditional breakpoints, and exception breakpoints.
Facts from Xdebug's own pages
- Browser integrations
- The step debugging documentation lists Xdebug Helper extensions for Firefox, Chrome/Chromium, and Edge, plus XDebugToggle for Safari. · xdebug.org, 2 Oct 2026
- Code coverage
- Xdebug provides code coverage analysis to show which parts of a codebase execute when running PHPUnit tests. · xdebug.org, 2 Oct 2026
- Compatibility
- Xdebug documents compatibility by PHP version and notes that current Xdebug releases support currently supported PHP versions. · xdebug.org, 2 Oct 2026
- Error reporting
- Xdebug improves var_dump() and adds stack traces for notices, warnings, errors, and exceptions. · xdebug.org, 2 Oct 2026
- IDE integrations
- The DBGp protocol is supported by nearly every PHP IDE, including Visual Studio Code and PhpStorm, and by text-based editors. · xdebug.org, 2 Oct 2026
- Networking
- Xdebug initiates debugger connections to the IDE, and Xdebug Cloud is described as a relay for cases where direct connections are blocked by networking or a firewall. · xdebug.org, 2 Oct 2026
- Product
- Xdebug is a PHP extension that provides features to improve the PHP development experience. · xdebug.org, 2 Oct 2026
- Profiling
- The built-in profiler reports execution and memory-use information in Cachegrind-compatible files that can be viewed with tools such as KCacheGrind or QCacheGrind. · xdebug.org, 2 Oct 2026
- Release limits
- The download page lists precompiled Windows binaries for specified PHP versions and source downloads for Linux and macOS. · xdebug.org, 2 Oct 2026
- Security and privacy
- The opened official pages describe debugging logs and connection configuration but make no security certification or compliance claim. · xdebug.org, 2 Oct 2026
- Step debugging
- Its step debugger lets developers walk through code interactively to examine control flow and data structures. · xdebug.org, 2 Oct 2026
- Support
- Community support uses Stack Overflow with low issue priority, while paid Pro and Business tiers offer email technical support and medium or high issue priority. · xdebug.org, 2 Oct 2026
- Supported systems
- Installation instructions cover Linux, macOS, Windows, and Unix-like systems; source builds are described for Unix-like operating systems. · xdebug.org, 2 Oct 2026
- Tracing
- Function tracing can record calls, arguments, and invocation locations, and optionally variable assignments and return values. · xdebug.org, 2 Oct 2026
Where Xdebug stands on Freedom251
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