Jayson is displaying the contents of a JSON file in an outline view.

Why is that such a big deal? Well you already know how to use an outline view since it is a standard macOS control used in Finder, Xcode and many other apps. You intuitively know how to use the most important features. Although there are many small hidden features that make your life easier.

What’s New

Version 1.8.1

• Fixed crash when editing the JSON document in the right-hand text editor (only certain cases)
• UI cleanup

Ratings and Reviews

3.5 out of 5
16 Ratings
16 Ratings
dopsonbr ,

Great Idea Needs Syntax highlighting

Good idea and has the potential to be pretty useful. Syntax highlighting is must. Without syntax highlighting its not worth using. I have spent years looking at JSON and XML files so by necccessity I became very profecient at reading those file types. However, it gets increasingly more difficult as those files grow in size. It is not uncommon to have to look through a 1000 line file and this is where your tool would provide me the most value. I would probably pay $10-20 per year if it supported some additional features: 1) Syntax highlighting 2) XML support 3) Handle curl/wget/httpie without me having to sanatize by supplying only the body 4) regex search support.

Derimagia ,

Solid Application, suggestion

The one suggestion I have that would make this more useful would be if you generated a launcher through a menu (Like any of the Jetbrain IDEs do, Sourcetree, etc) so that you can pipe json in and open it up. So you can make workflows that curl a json file, pipe it through jq to filter, and then pipe it into jayson to interact with it.

Slcc2c ,

Size limit?

I have a file with 5000 tweets stored as JSON objects, this program cannot open them. I get an error saying the file is not a JSON format because there is text after the closing ‘}’, I suspect the file stops processing in the middle of an object thus the error message.

Developer Response ,

You raised the question if there is a size limit. Short answer: No - not really.
Usually if Jayson reports a validation error the JSON file indeed not valid. Of course it is always possible that Jayson has a bug. Is it possible to send me the file in question? I would really appreciate getting my hands on this file so that I can fix a potential bug.


Christian Kienle
5 MB
Developer Tools

OS X 10.11 or later, 64-bit processor



Age Rating
Rated 4+
© Christian Kienle


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