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Preview of JSON Viewer

JSON Viewer by Dmytrii Lysak

A beautiful, customizable JSON/JSONP viewer and highlighter. Open-source fork: github.com/Lysak/json-viewer

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About this extension
It is a Chrome extension for printing JSON and JSONP.

Notes:
* This extension might crash with other JSON highlighters/formatters, you may need to disable them
* To highlight local files and incognito tabs you have to manually enable these options on the extensions page
* Sometimes when the plugin updates chrome leaves the old background process running and revokes some options, like the access to local files. When this happen just recheck the option that everything will work again
* Works on local files (if you enable this in chrome://extensions)

Features
* Syntax highlighting
* 27 built-in themes
* Collapsible nodes
* Clickable URLs (optional)
* URL does not matter (the content is analysed to determine if its a JSON or not)
* Inspect your json typing "json" in the console
* Hot word json-viewer into omnibox (type json-viewer + TAB and paste your JSON into omnibox, hit ENTER and it will be highlighted)
* Toggle button to view the raw/highlighted version
* Works with numbers bigger than Number.MAX_VALUE
* Option to show line numbers
* Option to customize your theme
* Option to customize the tab size
* Option to configure a max JSON size to highlight
* Option to collapse nodes from second level + Button to unfold all collapsed nodes
* Option to include a header with timestamp + url
* Option to allow the edition of the loaded JSON
* Option to sort json by keys
* Option for C-style braces and arrays
* Scratch pad, a new area which you can type/paste JSON and format indefinitely using a button or key shortcut. To access type json-viewer + TAB + scratch pad ENTER

This plugin is open source
https://github.com/tulios

Bugs and suggestions
https://github.com/tulios/json-viewer/issues

Contributors
Thiago Pontes (@thiagopnts)
@bluec0re
@North101
Ben Hollander (@benhollander)
Mehdi Bahrami (@mehdibahraami)
Reimund Trost (@reimund)
Ben van Enckevort (@benvan)

License
MIT License

Any questions tweet me @tulios
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Permissions and data

Required permissions:

  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
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Version
0.19.2025.1218
Size
1.01 MB
Last updated
6 days ago (Dec 18, 2025)
Related Categories
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License
MIT License
Version History
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