PRIVATE BROWSER TOOL

JSON Validator

Validate syntax and inspect document structure. Nothing is uploaded.

Input151 characters · 6 lines
Result0 characters · 0 lines

Run validation to inspect the document.

Processed locally on this device.
Unicode-safe UTF-8 handling

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LOCAL-FIRST TEXT UTILITIES

Private tools for every writing system.

Your text never leaves this browser. No uploads, accounts, or server processing.

Word segmentation uses your browser’s internationalization engine, with Unicode-safe handling across Latin, CJK, Hangul, Cyrillic, Arabic, Devanagari, and more.

About, editorial standards, and privacy

JSON TOOLS · LOCAL PROCESSING

Check JSON syntax and document structure locally

The JSON Validator parses your document in the browser and reports whether the syntax is valid. For valid input it also summarizes objects, arrays, keys, values, and nesting, which helps you check an unfamiliar payload before using it.

COMMON USES

When this tool is useful

  • Find a missing quote, comma, bracket, or other JSON syntax error.
  • Check a configuration file before committing or deploying it.
  • Get a quick structural summary of a large API payload.

THREE STEPS

How to use the JSON Validator

  1. Paste the complete JSON document into the input panel.
  2. Select Validate to parse the document in your browser.
  3. Use the result and structure summary to correct or confirm the source.

PRIVACY

Your input stays in this browser

The operation runs on your device and does not require the input to be uploaded. Copy and download actions happen only when you choose them. Avoid treating encoded output as encryption, and follow your own security requirements for confidential data.

WORKED EXAMPLE

JSON Validator: input and expected result

Input or settings

{"count":3,}

Expected result

Invalid JSON. Correction: {"count":3}

The comma after the final property makes the input invalid. Remove it and validate again; exact browser error messages vary.

METHOD & LIMITS

How the JSON Validator works

Processing method

Validation attempts JSON.parse. A successful parse is followed by a summary of root type, value nodes, nesting depth, and top-level items.

What to review

A syntax pass does not check a schema, required business fields, duplicate keys, or numeric precision. Use your application's own validation for those checks.

References: JSON data interchange format (RFC 8259)

PRACTICAL NOTES

What to know before using it

What counts as valid JSON?

Keys and string values require double quotes, commas cannot trail the last item, and the root must be a valid JSON value.

Is a valid result a schema check?

No. Syntax validation confirms that the document parses; it does not enforce a custom JSON Schema.