Tests.ws
WebSocket testing tools, protocol guides, and a Chrome extension for developers
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About Tests.ws
Tests.ws is a resource hub for developers working with WebSockets. It bundles an online tester, a free echo server, a Chrome extension, and a library of guides covering the WebSocket protocol across multiple programming languages. Everything is browser based and free to use.
The online tester lets you connect to any WebSocket server and send messages directly from your browser. You see incoming and outgoing frames in real time, which makes it useful for debugging connection issues, verifying payloads, or testing a server you are building. No installation is required, and you can get started by pasting a URL and hitting connect. For cases where you need a server to bounce messages back, the free echo server handles that so you can test client code without spinning up your own backend.
The Chrome extension adds monitoring capabilities on top of regular browsing. It proxies and inspects WebSocket traffic on any site you visit, which is helpful when you want to understand how a production application communicates in real time or when you are reverse engineering a protocol. This is a common workflow for developers building integrations or debugging issues in the wild.
Beyond the tools, Tests.ws publishes a set of guides covering WebSocket fundamentals and language specific implementations. There are walkthroughs for JavaScript, Python, Go, Rust, Java, and C#, along with documentation on the protocol itself. The content is educational rather than product focused, making the site a reference you can return to when you need to refresh on how something works or copy a code snippet.
There is no pricing because everything is free. The site is supported through a Patreon page and links to a GitHub repository for issue tracking and contributions. Support is community driven rather than commercial.
The audience is backend and frontend developers who work with real time communication. If you are building a chat system, a live dashboard, or any feature that relies on persistent connections, the testing tools and documentation here can save time during development. The browser first approach means you can start debugging without setting up a local environment or installing dependencies.
Key Features
- Browser based WebSocket tester
- Free echo server for testing
- Chrome extension for traffic monitoring
- Protocol documentation and guides
- Language tutorials for six languages
- Real time frame inspection
Pros & Cons
What we like
- Completely free with no signup required
- No installation for the online tester
- Chrome extension monitors any site
- Covers multiple languages in the guides
Room for improvement
- No commercial support or SLA
- Documentation depth varies by language
- Community driven updates may lag
- Focused narrowly on WebSockets only
Frequently Asked Questions
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Reviews (9)
Worth a look
Found Tests.ws on a Show HN thread and I am glad I clicked. Got real value out of real time frame inspection. It fits well for learning websocket implementations in new languages. Worth it for what I get out of it.
Exactly what I needed
Tests.ws has quietly become part of my daily flow. What stands out is how it handles covers multiple languages in the guides. It does what it says, which is rarer than it should be. Mostly using it for learning websocket implementations in new languages. Glad I made the switch.
Solid but not perfect
Picked Tests.ws for the price, stayed for the quality. The thing I keep coming back to is how reliable it is. The defaults are sensible, so I was not fighting settings on day one. Found it works best for debugging websocket server connections. The catch is no commercial support or sla. It earns its place in my stack.
Recommended without reservation
Found Tests.ws on a Show HN thread and I am glad I clicked. What stands out is how it handles free echo server for testing. Found it works best for monitoring live websocket traffic in chrome. Hard to imagine going back to my old setup.
Solid but not perfect
Picked Tests.ws for the price, stayed for the quality. What stands out is how it handles chrome extension for traffic monitoring. Performance has been steady even when I lean on it hard. It would be a five if not for focused narrowly on websockets only. It earns its place in my stack.
Solid daily driver
Found Tests.ws on a Show HN thread and I am glad I clicked. Got real value out of protocol documentation and guides. Found it works best for testing client code against an echo server. Would sign up again without thinking twice.
Two months in, no regrets
Have been running Tests.ws for a while, here is where I land. The free echo server for testing is more useful than I expected. It has shaved real time off my week. Found it works best for learning websocket implementations in new languages. Easy yes for anyone weighing the same trade offs.
Solid daily driver
Tests.ws has quietly become part of my daily flow. Where it really wins is covers multiple languages in the guides. Mostly using it for learning websocket implementations in new languages.
Quietly excellent
Found Tests.ws on a Show HN thread and I am glad I clicked. What stands out is how it handles covers multiple languages in the guides. Support actually answered when I had a question, which surprised me. Mostly using it for testing client code against an echo server. No regrets so far.
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