Where can I test if my webpage is responsive or not?

I want to know where i can test if my webpage is responsive or not.

Testing of responsiveness of webpage across different browsers and devices is necessary for better user experience. So first question comes in mind that How to test responsiveness of webpage ?

There can be many options to perform responsive testing. First one is to do it manually and second one is to do on cloud based testing tool with out establishing infrastructure setup.

There are many online platforms are available where you perform responsive testing on virtual desktop browsers and real devices. One such platform is LambdaTest.