Input
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Output
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JSON Syntax Error Debugger
Stop guessing. Paste your JSON and see the line, column, error type, and suggested fix in one view.
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Runs entirely in your browser — no upload, no wait.
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Your JSON never leaves the tab. Nothing is logged.
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Why generic JSON errors are useless
Browsers and Node throw the same vague "Unexpected token" message regardless of cause. The debugger turns the offset into a precise line/column with a snippet of context, then classifies the error: missing comma, unterminated string, bad escape, invalid number, control character, etc.
How to debug step by step
1. Paste the JSON. 2. Read the inline marker — it shows the exact character that broke parsing. 3. Hover the suggestion to see the recommended fix. 4. Click "Apply suggestion" to patch in place, or copy the suggestion into your source.
Multi-error mode
Most parsers give up at the first error. The debugger continues parsing speculatively to surface every error in one pass — useful when AI generators emit several issues at once.
Integrating into your editor
For VS Code, the same logic ships in the JSON Language Server (jsonc-parser). For CI, jq and ajv-cli give you the position; combine them with this tool for visual debugging.
# Quick CLI check
jq empty broken.json
# /broken.json:5: parse error: Expected separator between values at line 5, column 14Privacy
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