Developer Tools

JaSON

A simple, easy to use HTTP client to send API requests from within Chrome and see formatted, syntax highlighted responses.

View Chrome Web Store

Time on the storeAbout 10 years or moreA rough range, not an exact date

Store users≈4KRounded by the Chrome Web Store

Chrome Web Store rating4.5 / 538 ratings on the Chrome Web Store

Last store update3 Jul 2026Version 5.1.0, 3 months ago

Inside the extension

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Reviews

Mark Christopher13 months ago
I use this extension every single day, no kidding! It is simple and it works well. It formats the json response in a pretty format and when I copy the response it retains that nice formatting. The history is also extremely useful. I do not understand why google has now disabled this extension.
Mark Pearson3.8 years ago
This extension provided exactly what I was looking for - the ability to test an API which responds to HTTP POST requests with JSON responses. One feature I love is that it remembers previous requests which makes it very easy to fire off an earlier request again or change the JSON body of the request and then do the same. Excellent!
Gilbert Lopah4.1 years ago
I honestly love this extension <3
Semen Orlov4.4 years ago
Just doing what he has to do.
Developer C C8.7 years ago
Altamente recomendable
Chan Go8.7 years ago
Genial
Luis Enrique Flores Morales8.7 years ago
COOL
Nikhil Shah9.3 years ago
nice
Leonardo Isaac10 years ago
It's a very simple interface, it should work without any problem but I cannot make it work. No matter how I try to create my json data the parameters don't seem to reach the php. So sorry because I really need this kind of tool.
Xuezheng Fei11.9 years ago
cool.
Cutcsa Informatica12 years ago
Its OK, will be better if it could format the Json response in a more readable way (TreeView like an object).
Martin Haddad12.7 years ago
Awesome - use it everyday.. well done.
Steve Dodge13.5 years ago
Been using this for a couple of months now for all my JaSON based web services. Great Tool!
Chrome Web Store user13.6 years ago
works but doesn't really do what i need
Rahul roy14 years ago
i would say i loved it feature relating to json and formatiing . doesnt seem to work for xml in my case . its best in json