Result appears here after you select
{ } How to use
- Paste your JSON.
- Select Process to validate — errors show the line and column.
{ } How it works
JSON Validator works on the text you provide. Select Process ▸ and it runs entirely in your browser — nothing is uploaded to a server — then shows the result in the Output panel.
Input
- JSON input — paste or type your input in the left panel (use Sample for an example)
Output
TXT text — copy or download it from the Output panel.
{ } Common uses
- Find the line and column of a syntax error in a file a parser rejected.
- Confirm a generated or hand-edited document is well-formed before shipping it.
- Check what shape a document has at the top level — an object, an array or a bare value.
{ } Limitations
- This checks syntax only. It reports that the document parses, its root type and how many top-level entries it holds; it does not check the content against a schema. JSON Schema Validator does that.
- Comments and trailing commas are not JSON, so a file that relies on them is reported invalid rather than accepted. JSON Repair will fix those.
- The count is of top-level entries alone, so a deeply nested document reports a small number and says nothing about its depth.
{ } FAQ
Is my data uploaded to a server?
No. Everything runs locally in your browser — your files never leave your device.
Can I process more than one file at once?
This tool works on one input at a time.
Is this tool free?
Yes — it’s completely free and needs no sign-up.
It says invalid but I cannot see the problem.
Go to the line and column in the message and look just before it. The commonest causes are a trailing comma before a closing brace, a missing comma between two entries, single quotes instead of double, and an unescaped newline inside a string. If the file came from a language that permits those, run JSON Repair first.