How to Load Test Laravel Applications: Tools, Setup, and Real Results
More than seven years ago, I shipped a Laravel API that passed every unit test, every feature test, and every browser test I threw at it. The staging environment ran fine. Code review was clean. I deployed on a Friday afternoon, and by Monday morning, the app was returning 502s under 200 concurrent users.
The database connection pool was exhausted. File-based sessions were creating lock contention. A queued job that ran fine in isolation was stacking up 4,000 pending jobs because the worker couldn't keep pace with incoming requests. None of these problems showed up in testing because I'd never tested with more than one user at a time.
The company's first answer was to hire an external firm to run the load tests. The results were useful, but they arrived as a report from people who didn't know our codebase, and we couldn't rerun them after every change. So we brought load testing in-house with tools like k6, and got familiar with them ourselves. That exposed the real cost: the tooling lived outside PHP, so every new engineer we hired had to learn a separate language and toolchain before they could write a single test. With VoltTest, a PHP team goes from zero to a working load test in about two hours at most, because there's nothing new to learn.
That experience is why I built VoltTest, and it's why I'm writing this guide. Laravel load testing isn't optional if you're running anything beyond a personal project. This guide covers why Laravel apps fail under load, how the available tools compare, and how to set up and run real load tests using PHP: no JavaScript, no Python, no context-switching.
Laravel load testing catches failures that unit and feature tests miss: database bottlenecks, session contention, queue backlogs. VoltTest lets you write load tests in PHP, handles CSRF and cookies automatically, integrates with PHPUnit for CI/CD gating, and scales from local runs to thousands of concurrent users in the cloud. This guide walks through the complete setup.