Developer toolsRuns in your browserNested JSON support

JSON Formatter & Tree Viewer

Paste JSON and instantly format it into an expandable, collapsible tree. Type-based colors, search and filter, and parsing of nested JSON strings — built for inspecting HTTP requests and responses, with data never leaving your browser.

Great when you need to

Best for quickly viewing and debugging JSON, not for large-scale data editing.

You care about privacy and don't want to paste API data into a third-party site.

An escaped JSON string is nested inside an HTTP body and you want to expand it.

You work with a large response and want to search for a field or value and jump to it.

JSON input

0 characters

Paste JSON to get started

Paste JSON on the left and the formatted, collapsible tree will appear here.

Key features

Practical features built around inspecting HTTP requests and responses.

•Format on paste and render an expandable, collapsible tree
•Color values by type: string / number / boolean / null
•Search keys and values, highlight matches and auto-expand, with a matches-only mode
•Expand or collapse all nodes at once, and copy the formatted JSON
•Detect and expand JSON strings nested inside fields

How to use

Follow these steps to view your JSON.

1Paste or type JSON into the box on the left.
2The right side instantly formats it into a collapsible, color-coded tree.
3Use the search box to locate a field or value, and turn on “Matches only” if needed.
4For nested JSON strings, click the button on the node to expand them; copy the formatted result when you need it.

Notes

Good to know before you use it.

Nothing is uploaded — parsing and search run entirely in your browser.

Standard JSON is supported; comments, trailing commas and other non-standard syntax will fail to parse.

Expanding a very large JSON fully can be slow — collapse it first or use search to navigate.

FAQ

A few common questions before you start.

Is my JSON uploaded to a server?

No. Parsing, formatting and search all happen locally in your browser; your data is never sent to a server.

What happens if my JSON is invalid?

It shows why parsing failed and pinpoints the exact line and column so you can fix it quickly.

What does “parse nested JSON strings” mean?

HTTP responses often store a chunk of JSON as a string inside a field. When such a string is detected, you can click a button to expand it into a subtree.