As a WordPress user, site owner, or developer, having access to debugging tools is crucial for diagnosing issues before they spiral into bigger problems. With over 455 million websites now running on WordPress and extensive flexibility through plugins/themes, the potential for performance problems or full-on crashes is always there.
Even minor hiccups like 2-second slowdowns can devastate page load speeds. According to Google research, as little as a 100 millisecond delay leads to a 25% drop in sessions/users across all verticals analyzed.
Simply put – website delays are extremely toxic. Without debugging tools to troubleshoot problems, you‘ll likely experience cascading losses in organic visibility, user retention, and revenue over time.
That‘s why having a robust debugging toolkit you can rely on is so vital for WordPress success. In this guide, we’ll cover 7 standout options that every site owner should have familiarity with:
- WP_DEBUG – Built-in WordPress debugging
- Database Reporting – Log all database queries
- Staging Sites – Safe isolated testing/debugging
- Query Monitor – Developer toolkit for diagnostics
- Firefox DevTools – Advanced JS/CSS debugging
- New Relic APM – Enterprise-scale monitoring
- Debug Bar – Rapid debugging via admin toolbar
Let‘s explore what makes each of these WordPress debugging tools so uniquely valuable.
An Ounce of Prevention: The Critical Importance of Debugging
Before we dive further into the tools, it‘s worth underscoring why debugging is so essential for WordPress users of all skill levels.
As the saying goes: "An ounce of prevention is worth a pound of cure." The costs – both in terms of time and site stability – rapidly multiply if issues are allowed to escalate unchecked.
Common WordPress problems like plugin conflicts, exhausted server resources, bloated databases, or inefficient code can cripple site performance and user experience if not addressed early on.
Without debugging tools to monitor for warnings or quickly isolate the root causes once problems emerge, troubleshooting is painful and tedious even for experts. Resolution times drag on while visitors encounter frustrating lag, errors, or outages.
Mundane issues easily snowball into loss of organic visibility, traffic, signups, and revenue. The compounding growth you worked so hard to achieve reverses at an alarming rate.
Conversely, leveraging debugging toolkits lets savvy WordPress users, developers, and site owners:
- Identify performance hotspots before they become user-facing problems
- Nip emerging issues in the bud through proactive alerts
- Rapidly diagnose tricky bugs that evade basic troubleshooting
- Optimize web vitals like site speed that impact organic rankings
- Pinpoint rogue plugin/theme/code choking resources
- Monitor infrastructure capacity constraints
- Quantify business costs of technical shortfalls
- Justify priority upgrades/fixes through data-driven insights
In short – stepping up your debugging game with the tools below helps drive resilience, continuity, and results. Let‘s explore the top options available now.
1. WP_DEBUG – Built-In Logging of Errors & Notices
The simplest way to enable basic debugging in WordPress is through WP_DEBUG. This constant, when activated in wp-config.php, logs various warnings, notices, and fatal PHP errors into a debug.log file.
To enable:
define( ‘WP_DEBUG‘, true );
define( ‘WP_DEBUG_LOG‘, true );This captures errors without exposing them on the front-end. WP_DEBUG_DISPLAY can also be set to true show errors on-screen, but should never be used for live sites.
Reviewing logs from WP_DEBUG alone provides limited insights. But combined with other debugging tools, these error notices help piece together wider issues.
As WordPress core advisor Otto 42 notes, "On its own, WP_DEBUG doesn’t tell you much…it shows you what broke, not why."
Still, it offers a useful starting point before digging deeper. Just ensure debugging gets disabled again once resolved – leaving it active poses security risks!
2. Database Debugging – Inspect Queries Causing Slowness
Database problems are another leading cause of WordPress performance woes. Sluggish queries, bottlenecks, and growing tables can grind sites to a halt.
By enabling database debugging, we can log all database queries for inspection:
define( ‘SAVEQUERIES‘, true );Then display them via:
global $wpdb;
print_r( $wpdb->queries ); Isolating expensive queries built by rogue plugins/themes lets us target specific causes versus guessing randomly.
According to Kinsta, "debugging database queries is crucial…identifying and fixing just one slow or duplicate query can significantly improve site speed."
As usual, disable debugging once resolved. On high-traffic sites, leaving this active may generate excess database load itself!
3. Staging Sites – Safely Debug in a Sandbox
‘‘‘Staging sites‘‘‘ mirror your live site into a safe testing sandbox. They represent one of the most useful tools for debugging WordPress safely without impacting real users.
The ability to precisely replicate production environments is extremely valuable for diagnosing bugs, doing dry-runs of upgrades, or experimenting with new functionality.
Many managed WordPress hosts include staging sites for free with higher-tier plans. For example, Kinsta‘s staging tools enable cloning live sites with a single click. Automated daily syncing also keeps staging in parity with production.
Standalone plugins like WP Staging offer similar capabilities. These let you create staging sites manually on existing hosting accounts that lack native support.
Either way, leveraging staging during debugging lets you safely:
- Test cutting-edge beta software
- Experiment with radical theme changes
- Model production data/traffic at scale
- Mirror collaboration across teams
- Accelerate repair of crippled sites
- Isolate “works on staging but not live” defects
Baking staging sites into your debugging workflow saves massive headaches down the road.
4. Query Monitor – All-in-One Developer Toolkit
For hardcore debugging data, Query Monitor is an open-source developer toolkit packing tremendous value. It surfaces an array of diagnostics for both frontend and backend WordPress:
⛔️ Errors & warnings
⚙️ Hooks & actions
📊 Performance metrics
🖥️ HTTP requests
📈 User capability checks
🔍 PHP debugging
💾 Database queries by plugin/theme
👥 REST API calls
📦 Cache efficiency
And more!The admin toolbar menu provides live debugging stats for the current page load. Developers can interactively inspect everything powering each request behind the scenes.
For example, aggregating database queries by offender makes it easy to identify plugin/theme culprits choking database performance.
Similarly, tracking execution time and memory usage per plugin reveals code bottlenecks. Optimizing or replacing these boosts site speed.
Both novices and experts alike appreciate Query Monitor‘s wealth of aggregated diagnostics for rapid troubleshooting.
5. Firefox Developer Tools – Frontend Debugging Powerhouse
Firefox Developer Tools (formerly Firebug) sets the gold standard for deep JavaScript, CSS, and frontend debugging.
With detailed network inspection, UI element examination, script stepping, memory profiling and more, it‘s an indispensable toolkit for diagnosing front-end issues:
☢️ Inspector Tool
- Inspect/edit any HTML/CSS in the browser
- See CSS changes applied instantly without page refreshes
- Remotely debug mobile Firefox sessions
🐞 Web Console
- View JavaScript errors, warnings, debug logs
- Inspect network requests with timing/status details
- Interactively test frontend code in the console
⚡ Page Source Mapper
- Set breakpoints and step through JavaScript execution
- Map minified/bundled production code back to original files
- Improves context for debugging obfuscated code
For all its strengths, Firefox DevTools does require strong JavaScript fluency to leverage fully. But for developers, it‘s arguably the most versatile browser-based debugging toolkit available.
6. New Relic APM – Premium Performance Monitoring
New Relic APM (Application Performance Monitoring) takes production monitoring to the enterprise scale. As one of the largest APM solutions, it offers extensive capabilities like:
‘‘‘Real-time performance dashboards‘‘‘
-
Interactive graphs show metrics for overall site health:
- Load times & server response rates
- Peak traffic & daily cycles
- Error rates & uptime plots
- Database/cache/CDN efficiency
‘‘‘Proactive alerting and notifications‘‘‘
-
Configure thresholds and alarms for:
- Network latency
- Sudden traffic changes
- Error spikes
- Hosting environment issues
-
Get emailed, texted, or called for urgent alerts
‘‘Forensics tools and distributed tracing‘‘
- Distributed tracing maps complete end-to-end request flows across all infrastructure and codepaths
- Measure how each application layer contributes to overall latency
- Identify chokepoints across services slowing requests
For large-scale WordPress deployments, New Relic’s premium capabilities accelerate root cause analysis for obscure bugs. Reviewing dashboard metrics also aids proactive optimization.
But with prices from $9 to over $200 a month, the solution better suits agencies versus small sites. Individual developers may find open source alternatives like Skylight or Speedscope sufficient.
7. Debug Bar & Companion Plugins – One-Stop Diagnostics Shop
Debug Bar packs tremendous value as a centralized launchpad for various debugging tools through the admin bar UI.
The base module and 50+ companion plugins surface integrated insights around:
- ⚒️ Debug Bar Cron – Hooks/schedules for wp-cron events
- 🖥️ Debug Bar Constants – Defined constants
- ⌨️ Debug Bar Console – Interactive PHP console
- 📦 Debug Bar Object Cache – Object cache efficiency stats
- 🔗 Debug Bar Actions/Filters – Hooks triggered during page load
Rather than forcing developers to access standalone tools separately, Debug Bar neatly consolidates key data points into one screen for triaging.
The multitude of extension plugins available further expands its capabilities. Whether debugging complex cron scenarios, AJAX calls, transients, or REST API traffic, Debug Bar aims to provide expanded context beyond raw debugging logs.
For both WordPress experts and novices, it simplifies initial issue spotting. Download Debug Bar from the official repository to give it a try firsthand.
Level Up Your WordPress Debugging Skills
Learning to leverage debugging tools effectively takes practice. But doing so pays dividends through added assurance, continuity, and performance.
Even non-developers can watch for red flags indicating problems – sudden drops in Google Analytics, upticks in 404 errors, sluggish page loads, etc. Consider staging sites to safely test changes too.
Should problems emerge, providing debugging data accelerates troubleshooting rather than leaving developers clueless. Basic tools like Debug Bar or Query Monitor are fairly intuitive to deploy.
For developers, investing time to master advanced environments like Firefox DevTools directly correlates to debugging proficiency. Tracing front-end performance regressions back to recent code commits becomes possible.
Regardless, debugging skills allow all WordPress users to spend less time firefighting avoidable issues. Instead that energy gets redirected towards unlocking creativity, testing innovations, and conducting higher-impact work.
Here‘s to a faster, less frustrating future of building awesome WordPress-powered sites!
