What is WebSurge?
West Wind WebSurge is a Windows-first HTTP load and stress testing tool built by Rick Strahl. It captures requests from Fiddler or a built-in proxy, parameterises them in a session file, and replays them at configurable concurrency from a desktop GUI or command line. WebSurge is popular with .NET developers who need a lightweight, scriptable HTTP load tester they can run locally without spinning up cloud infrastructure.
WebSurge is a focused tool: HTTP request capture, parameterisation, replay, and result inspection. It is not trying to be a full performance platform — no browser tests, no scheduled monitoring, no API uptime alerts, no Core Web Vitals.
When WebSurge is the right tool
WebSurge is a sensible pick when your workflow is:
- Local HTTP load checks on Windows. A developer running "does this endpoint hold up at 200 concurrent users?" from a laptop.
- Fiddler-captured replay. Reusing existing Fiddler sessions to load test specific request flows.
- Small-scale, throwaway tests. Quick verification before a deploy without provisioning cloud agents.
If you want a single-machine HTTP tool that integrates with a Windows developer workflow, WebSurge does that well.
Where WebSurge stops being enough
WebSurge's scope is intentionally narrow, and that becomes the gap when testing needs grow:
- Windows-first, desktop-bound. Single-machine concurrency caps out long before realistic production load.
- No browser-based testing. Modern web apps depend on JavaScript-rendered flows that HTTP replay cannot reproduce.
- No API monitoring or alerts. WebSurge runs tests on demand; continuous uptime and SLA monitoring need a separate tool.
- No Core Web Vitals tracking. Page speed and Lighthouse audits are out of scope.
- No team collaboration / shared dashboards. Results stay local to whoever ran the test.
LoadFocus vs WebSurge — feature comparison
How LoadFocus compares against a typical WebSurge desktop deployment. Pricing accurate as of May 2026.
| Feature | LoadFocus | WebSurge |
|---|---|---|
| Cost | Free tier; from $29/mo | One-time license |
| Cloud-based execution | Yes (no install) | No (Windows desktop) |
| Concurrent virtual users | Up to 12,500 VUs | Limited by local machine |
| Browser-based load testing | Yes (Selenium/Playwright) | No |
| API monitoring | Yes | No |
| Core Web Vitals monitoring | Yes | No |
| Scheduled tests / alerts | Yes | No |
| Multi-region test locations | 25+ globally | Single machine |
| Team collaboration / shared reports | Yes | Local files |
| CI/CD integration | Yes (API + GitHub Action) | Command line |
FAQ
Is LoadFocus a direct replacement for WebSurge?
For developer-led HTTP load testing, yes — and it lifts the ceiling on concurrency, locations and reporting. WebSurge is fine for small local checks; LoadFocus covers the same ground plus browser tests, API monitoring and team dashboards on the same account.
Can we import existing Fiddler sessions?
LoadFocus supports JMeter (JMX), HAR files and direct URL/recording, so most Fiddler-captured flows can be replayed with light conversion. The recorder also lets you re-capture a flow in minutes if conversion is not worth the time.
What about test concurrency limits?
WebSurge concurrency is capped by the local machine and network. LoadFocus distributes load across cloud agents up to 12,500 virtual users, so you can run realistic production-scale tests without provisioning hardware.
How does pricing compare?
WebSurge is a one-time license for a single user, on a single machine. LoadFocus uses transparent monthly tiers from $29/month and includes load testing, API monitoring and page speed on the same account, which usually replaces multiple specialised tools.
How long does setup take?
Minutes. Sign up, paste a URL or upload a JMX, pick a load profile and run — no agents to install, no Windows machine required.
Can it run in CI/CD?
Yes. LoadFocus exposes a REST API and a GitHub Action so load tests run on every merge with thresholds on response time, error rate and concurrency. WebSurge can be scripted from the command line but lacks a hosted dashboard.
Try LoadFocus free
If WebSurge is your daily HTTP load tool but you're hitting the ceiling on concurrency, browser testing or shared reporting, LoadFocus covers the same ground from the cloud. Sign up at loadfocus.com/signup — no credit card — and run your first cloud load test in minutes.
