If you’re a developer, chances are you spend half your day wrestling with APIs. Frontend, backend, full-stack—it doesn’t matter. APIs are everywhere, and debugging them is as essential as coffee in the morning.
For years, Postman was the default hammer for every API nail. But let’s be real: it’s bloated, it hogs memory, and firing it up feels like starting a small operating system. That’s why developers are flocking to lightweight VS Code extensions that let you test APIs without ever leaving your editor.
Two names keep coming up: Thunder Client and the newer challenger, EchoAPI. Both live inside VS Code, both help you debug APIs—but the similarity ends there. One is a nimble utility knife; the other is basically an armored tank with Wi-Fi.
So… which one should you use? Let’s break it down.

Think of Thunder Client as the diet version of Postman. It strips away the fluff and focuses on the basics: sending requests, viewing responses, and doing it all fast. It’s built for solo devs who don’t want overhead, documentation bloat, or collaboration gimmicks—just clean, quick debugging.
EchoAPI, on the other hand, said: “Why not go big?” It’s a one-stop shop that bundles API debugging, documentation generation, automated testing, code snippets, offline support, and even team collaboration—directly inside VS Code. Imagine Postman + Swagger + a testing framework all rolled into one, minus the desktop app headache.
👉 In short:
Here’s the tale of the tape:

👉 Translation: EchoAPI is the buffet; Thunder Client is the snack bar.
Thunder Client: Starts in seconds, light as a feather, and looks almost like Postman—zero learning curve. Perfect for a “hit-and-run” debugging session.
EchoAPI: A bit more panels, a bit more weight, but still miles lighter than Postman. The payoff is huge: you get documentation, testing, and collaboration without juggling five different tools.
Both tools can handle the classic login → fetch user info flow. The difference is in how much effort it takes.
In Thunder Client, you’ll send the login request, manually set up assertions, grab the token with a script, and reuse it for the user info endpoint. It works—but feels like doing laundry by hand.
In EchoAPI, token extraction is one click. Assertions live in the panel. You can wrap the whole thing in a collection, run automated tests, and even generate a shareable report. It’s like having a washing machine that also folds your clothes.
Winner: EchoAPI, hands down.
At the end of the day, it’s all about what you need:
Either way, both extensions let you escape the clunky gravity of Postman and keep everything inside VS Code—where it belongs.
👉 If you want speed and simplicity, grab Thunder Client.
👉 If you want power and team-ready workflows, EchoAPI is your new best friend.