Technical interview questions and answers are critical when preparing for an AJAX Interview because companies want to evaluate your understanding of asynchronous communication, XMLHttpRequest, JSON handling, DOM manipulation, and interactive web applications. AJAX is considered a core concept in modern web development, and many companies include it as part of their technical rounds for frontend and full-stack developer roles. Organizations like TCS, Infosys, Wipro, Cognizant, and Capgemini frequently ask AJAX-related questions to check whether candidates can build dynamic, responsive, and efficient web pages. This guide includes commonly asked AJAX interview questions with clear explanations to help freshers and job seekers strengthen their web development fundamentals. These questions will improve your preparation for placement interviews, coding rounds, and real-time project discussions.
Showing 10 of 193 questions
1. When should AJAX NOT be used?
It would not be appropriate to use AJAX when the answer/result? can be determinded by the client. Generally, the purpose of AJAX is to submit a short request to the server,and process the response in such a way as to add value to the currently displayed page.It would also not be appropriate to use AJAX when the magnitude of the response is such that it would be easier, and more clear to redisplay the page.
2. How do you know that an AJAX request has completed?
The XHR.readyState is 4 and the XHR.status is 200 (or zero if the request is to a local file). The callback function is called four times first with status=1, then 2,3, and finally 4.
3. How does XML processing differ on the different browsers?
Its an ActiveX object on IE, but is native on the other browsers
4. Is it possible to achieve similar results without the XmlHttpRequest object?
A hidden IFrame (actually an IFrame of size 0px * 0px due to a bug in IE) can be used to retrieve data, and its contents can then be processed in a similar manner to the response from an XHR call.
5. Is AJAX a programming language?
No
6. What is AJAX?
In one sense, AJAX is simply an acronym for “Asynchronous JavaScript And XML” In another, it is a protocol for sending requests from a client (web page) to a server,and how the information is / should be communicated between the client and the server
7. How new is AJAX?
The terminology is new, but the techniques are not.
8. Why can/should AJAX be used?
AJAX is best suited for small (hopefully unobtrusive) updates to the current web page, based on information that is not available until it has been provided by the end user.
9. Describe some things that cant be done with AJAX
Sending a request to a server outside of the domain from which the web page originated.