What does this tool report?
The JSON Analyzer combines several checks into one report: structural counts (objects, arrays, keys), a breakdown of value types, maximum nesting depth, overall size, the five most frequently used keys, and a scan for duplicate keys within the same object.
How to use this tool
- Paste your JSON into the left-hand box.
- Click Analyze JSON.
- Review the full report, including any duplicate key warnings.
Frequently asked questions
How is this different from JSON Statistics?
JSON Statistics gives you the structural counts and type breakdown. JSON Analyzer includes all of that plus the top 5 most frequently used keys and a duplicate-key check, giving a more complete picture in one report.
How does it detect duplicate keys?
It scans the raw text structurally (not just via JSON.parse, which silently keeps only the last value) to catch cases where the same key appears twice within a single object — almost always a mistake.
Is my JSON uploaded anywhere for analysis?
No — the entire analysis runs locally in your browser using JavaScript. Nothing is sent to a server.