Format and validate JSON you paste, processed on-device, with no access to your browsing. Tree, convert, and diff are premium.
Users
8
+3 in 30 days
Rating
0.0 / 5
unchanged in 30 days
Ratings
0
0 in 30 days
Store rank
#215K
#180K among extensions
Version
0.1.2
updated 30 Aug 2026
Users
monthly, 3 months
Latest, 16 Oct 2026:8 usersMove the mouse over the chart for any month
Ratings count
monthly, 3 months
Latest, 16 Oct 2026:0 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 JSON Formatter: Paste & Validate
JSON formatter, validator & beautifier. Paste JSON, get instant output
This is a paste-in, paste-out JSON tool that formats, validates, and
beautifies JSON without ever touching the page you're on.
PRIVATE BY DESIGN
This extension asks for zero access to your browsing. There are no
content scripts and no host permissions, so it cannot read the tabs
you have open, the sites you visit, or anything on the page. You
open the popup, paste JSON in, and get formatted output back. Every
byte of processing (parsing, formatting, validation, highlighting)
happens locally in your browser. Nothing you paste is ever sent
anywhere. This extension collects no data of any kind: no
analytics, no tracking, no telemetry. The only network traffic it
ever makes is a purchase-verification check with ExtensionPay if
you choose to upgrade.
FREE, AND GENUINELY USEFUL
- Format: pretty-print with your choice of 2-space, 4-space, or tab
indent, applied instantly as you paste.
- Validate with exact error location: invalid JSON gets a precise
line and column, a caret pointing at the exact character, and a
plain-English explanation (like "trailing comma before }") instead
of a cryptic parser message.
- Syntax highlighting on the formatted result, so nested structures
are easy to scan.
- Minify with one click when you need compact output.
- Sort keys recursively to make two JSON blobs easier to compare by eye
or normalize inconsistent API responses.
- Copy the result to your clipboard or download it as a file.
- Your indent style, sort-keys default, and light/dark theme are
remembered between sessions.
PREMIUM ($5 one-time)
For people who work with JSON all day, a one-time $5 upgrade adds:
- A collapsible tree view with search/filter and one-click copy of
any node's JSON path.
- JSON to CSV and JSON to YAML conversion, both directions.
No subscription, no account required, no recurring charge. Pay
once, keep the premium features.
Inspect an API response, clean up a config file, debug a webhook
payload. This extension does the job without ever asking to see
what's on your screen.