Extensions Reloader
Developer ToolsFree
Reload all unpacked extensions using the extension's toolbar button or by browsing to "http://reload.extensions"
4.4141 reviews10K+
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JSON Formatter
Makes raw JSON responses readable in the browser.
4.32,100 reviews~2M+ usersDeveloper ToolsBy Callum Locke
Free
Reviewed by the Single Tab Browser editorial teamLast tested 2026-04-30JSON Formatter screenshots
Overview
JSON Formatter pretty-prints JSON API responses with syntax highlighting, collapsible nodes, clickable URLs and a raw/parsed toggle, replacing an unreadable wall of text.
JSON Formatter is a developer tools Chrome extension from Callum Locke with roughly 2M users on the Chrome Web Store. It holds a 4.3-star average across 2K ratings, which puts it among the better-reviewed options in its category. Pricing is free.
JSON Formatter pretty-prints JSON API responses with syntax highlighting, collapsible nodes, clickable URLs and a raw/parsed toggle, replacing an unreadable wall of text.
The trade-off is the usual one for a free extension: there is no paid tier to unlock, so anything missing is simply missing. With 2M users, complaints and fixes surface quickly, so check the review notes below before installing it alongside other developer tools extensions.
How to install and set up JSON Formatter
- 1Open the Chrome Web Store listing for JSON Formatter and click Add to Chrome, then Add extension.
- 2Pin the icon: click the puzzle-piece button in Chrome's toolbar, find it in the list and click the pin so it stays visible.
- 3Open the extension once and walk through its first-run screen — a developer tools extension usually asks which sites it may act on.
- 4Test it on a page you know well before relying on it for daily work.
- 5To remove it later, right-click the toolbar icon and choose Remove from Chrome, or use chrome://extensions.
Key features
JSON Formatter pretty-prints JSON API responses with syntax
JSON Formatter pretty-prints JSON API responses with syntax highlighting, collapsible nodes, clickable URLs and a raw/parsed toggle, replacing an…
Who should use JSON Formatter?
Anyone poking at REST APIs directly in the browser.
Pricing
JSON Formatter is free. There is no paid tier to consider.
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View ExtensionFrequently asked questions
Is JSON Formatter free?
Yes. JSON Formatter is listed as free on the Chrome Web Store with no paid tier.
How many people use JSON Formatter?
Roughly 2M Chrome users have it installed, and it holds a 4.3-star average from 2K ratings.
Is JSON Formatter safe to install?
JSON Formatter is published on the official Chrome Web Store by Callum Locke, so it passes Google's review. Check the permissions it asks for on install and prefer the store listing over third-party mirrors.
What are the best JSON Formatter alternatives?
The alternatives page lists the closest developer tools extensions ranked by installs and rating, with a head-to-head comparison for the top pick.
Related extensions to JSON Formatter
Picked from the Developer Tools category and the tags json, api, developer — jump straight to the alternatives and head-to-head pages people open next.
Best Developer Tools Chrome extensionsExtensions Reloader alternativesReload all unpacked extensions using the extension's toolbar button or by browsing to "http://reload.extensions"Wappalyzer alternativesIdentifies the technology stack behind any website.Web Developer alternativesAdds a toolbar button with various web developer tools.Web Scraper alternativesPoint-and-click scraper that exports site data to CSV.Wappalyzer vs JSON FormatterEssential developer Chrome extensions?React Developer Tools vs JSON FormatterReact Developer Tools or JSON Formatter: which should I install?React Developer Tools vs WappalyzerReact Developer Tools or Wappalyzer: which should I install?All Developer Tools extensionsEvery developer tools extension in the directory, ranked.
Compare JSON Formatter with the obvious rivals
Side-by-side feature tables, pricing and a clear recommendation.
Wappalyzer vs JSON FormatterStack detection for recon work against readable API responses in the browser.React Developer Tools vs JSON FormatterBoth are developer tools extensions people shortlist together — see how ratings, install base, pricing and day-to-day use differ.JSON Formatter vs Web DeveloperHead-to-head breakdown with real install and rating data.JSON Formatter vs WappalyzerHead-to-head breakdown with real install and rating data.React Developer Tools vs JSON FormatterHead-to-head breakdown with real install and rating data.JSON Formatter alternativesRanked replacements if JSON Formatter is not the right fit.All comparisonsThe full compare hub, grouped by category.