What does "unexpected token" mean in JSON?

The parser found a character it did not expect at that position. Common causes: single quotes instead of double quotes, an unquoted key, a JavaScript comment, a trailing comma, or a stray character from copy-paste.

How do I find which token is unexpected?

The error message usually includes "at position N" — count N characters into your JSON to find the problem character. JSONBlitz highlights it automatically and shows what was fixed in the Diff tab.

Does the position number in the error help?

Yes but it counts from the start of the string, not the line. For large JSON, use the Diff tab — it shows which specific lines were changed and why.

Can JSONBlitz fix all unexpected token errors?

Most of them — single quotes, unquoted keys, JS comments, trailing commas, Python booleans, smart quotes, and control characters are all handled. If the error is a typo in a value, that requires manual correction.

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Frequently Asked Questions

What does "unexpected token" mean in JSON?: The parser found a character it did not expect at that position. Common causes: single quotes instead of double quotes, an unquoted key, a JavaScript comment, a trailing comma, or a stray character from copy-paste.
How do I find which token is unexpected?: The error message usually includes "at position N" — count N characters into your JSON to find the problem character. JSONBlitz highlights it automatically and shows what was fixed in the Diff tab.
Does the position number in the error help?: Yes but it counts from the start of the string, not the line. For large JSON, use the Diff tab — it shows which specific lines were changed and why.
Can JSONBlitz fix all unexpected token errors?: Most of them — single quotes, unquoted keys, JS comments, trailing commas, Python booleans, smart quotes, and control characters are all handled. If the error is a typo in a value, that requires manual correction.