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JSON Viewer

Parse, format, and explore JSON data through a collapsible tree view with expand and collapse controls at every nesting level. Supports beautification, minification, key and value search, file upload, and structural depth statistics for rapid document inspection.

Runs entirely in your browser

This tool sends nothing over the network. Everything you enter is processed on your device and never reaches our servers.

Data
Testing
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Reference

Documentation

A JSON viewer parses raw JSON text, or a loaded .json file, into a collapsible tree that mirrors the document's structure: each object and array becomes a toggleable node, so a deeply nested structure can be drilled into without losing the surrounding context. Keys, strings, numbers, booleans, and null values are each rendered with distinct markup, so the data type behind a value is visible at a glance rather than inferred from its formatting.

An invalid document produces an error notification naming the parse error and its approximate location rather than a blank tree. Expand All and Collapse All toggle every node at once, useful for a quick overview versus a detailed pass through one branch. A search field highlights matching keys and values throughout the tree; branches containing a match stay visible while non-matching branches collapse, which narrows a large document down to the parts that are actually relevant.

Beautifying reformats the raw input with consistent indentation; minifying compresses the same JSON onto a single line with no whitespace, useful for pasting into an API request or a configuration field that expects a single value. Indent size (2, 4, or 8 spaces, or a tab) controls the beautifier's output, and a default collapse depth setting controls how many nesting levels render expanded when a document is first loaded.

A statistics section reports the total number of keys, the maximum nesting depth, the total number of values, and the byte size of the raw input, giving a structural summary of a document without reading through it line by line.

Structured JSON data appears throughout software development, data engineering, API integration, and configuration management. A dedicated viewer that renders collapsible trees, provides search, and reports structural statistics accelerates debugging and review workflows across many domains.

  • API Development: Inspect response payloads from REST or GraphQL endpoints to verify field names, nesting structure, and data types before writing client-side parsing logic.
  • Configuration Review: Load application configuration files (package.json, tsconfig.json, Terraform state) to explore settings hierarchies and confirm values without opening a code editor.
  • Data Engineering: Examine exported dataset samples in JSON format to validate schema consistency, check for unexpected null values, and measure nesting depth before building ETL pipelines.
  • Quality Assurance: Compare expected and actual JSON outputs during test runs by beautifying both with the same indent settings, making structural differences visible in a side-by-side diff.
  • Education: Demonstrate JSON data structures to students with example objects and arrays, expanding and collapsing branches to illustrate how nested data maps to programming language constructs like dictionaries and lists.
  • Log Analysis: Parse structured log entries emitted in JSON Lines format one record at a time, using the search filter to locate specific request IDs, error codes, or timestamps within verbose payloads.
  • Database Administration: Inspect BSON-exported MongoDB documents or CouchDB responses to verify document structure, embedded arrays, and reference fields without running additional queries.
  • DevOps and Infrastructure: Review Kubernetes resource definitions, AWS CloudFormation outputs, or CI/CD pipeline artifacts stored as JSON to trace configuration values across multi-level nesting before applying changes to production environments.
Inputs, outputs, and what the JSON Viewer computes

What the JSON Viewer asks for and what it returns, as a plain list. Defaults, units, and ranges are the ones the form loads with.

Inputs

  • Paste or type JSON below
  • Indent Size · default: 2 spaces
  • Default Collapse Depth (numeric input) · default: 2 · range: 0 to 50
  • Filter keys or values (text input)

Controls

Reset · Copy Formatted