JaSON icon

JaSON

by Shane Bell · Developer Tools
Manifest V3 Free
View in Chrome Web Store Data as of 15 Oct 2026

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

Users
4,000
0 in 30 days
Rating
4.5 / 5
unchanged in 30 days
Ratings
38
0 in 30 days
Store rank
#15K
#13K among extensions
Version
5.1.0
updated 3 Jul 2026

Users

monthly, 3 years
1,0004,5008,000Aug 2023Apr 2025Oct 2026
Latest, 15 Oct 2026: 4,000 usersMove the mouse over the chart for any month

Ratings count

monthly, 3 years
102643Aug 2023Apr 2025Oct 2026
Latest, 15 Oct 2026: 38 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About JaSON

Great for testing and debugging JSON and XML APIs, RESTful APIs, GraphQL APIs, web services, web applications and more. Cookie support: Automatically sends cookies from Chrome. This is extremely handy for APIs which require authentication. Simply authenticate via your browser as normal and JaSON will send cookies for requests which match. HTTP methods: GET, POST, PUT, PATCH, DELETE, HEAD, and OPTIONS Dark/light theme: Change the colour theme to suit your work environment. Request history: Keeps request history with full text search. Individual history items can be deleted, or marked as a "favourite" for easy access. History from previous versions of JaSON will be automatically migrated. Stores history in IndexedDB for improved performance. Formatted input/output: Provides an IDE like experience when editing request body and headers. Automatically formats request/response body syntax and colour based on content type. Content type: Supports JSON, XML, and form encoded data by default. Additional content types can be used by setting a custom content type header. New and improved: Completely re-written, new styling, layout, colours, additional features and improved performance. 100% open source Source code is available from GitHub. Privacy policy https://github.com/shanebell/JaSON/blob/master/privacy-policy.md

Growth

WindowUsersChangeRatingsRating
7 days0+0.0%00.00
30 days0+0.0%00.00
6 months+1,000+33.3%00.00
1 year0+0.0%−1+0.09

Version history

6 versions recorded
5.1.03 Jul 2026
5.0.2523 Apr 2021
5.0.2419 Apr 2021
5.0.2331 Jan 2021
5.0.1530 Oct 2020
5.0.1328 Jun 2020

Details

Category
Developer Tools
First seen
28 Jun 2020
Size
1.1 MB
Languages
en-US
Pricing
Free
Privacy policy
github.com
Support
github.com
Extension ID
oealdlhfjifhgbmjnenhkgffglaibojf

Permissions and risk

Moderate riskimpact 2, likelihood 2
Site access
http://*/*https://*/*
Can read and change data on every website you visit.

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