Unquoted string value in JSON
A value that is neither a number, `true`, `false`, `null`, an object nor an array must be a quoted string.
The input
{"a": hello}{"a": "hello"}How to fix it
Wrap the value in double quotes.
Templated documents cause this when a substituted variable is not quoted in the template.
What each parser reports
Every message below was captured by running this exact input through the parser named. 19 of 21 parsers rejected it; 2 accepted it.
| Parser | Exact message |
|---|---|
| CPython json.loads CPython 3.12.3 | Expecting value: line 1 column 7 (char 6)what this message means → |
| encoding/json Unmarshal Go go1.22.2 | invalid character 'h' looking for beginning of valuewhat this message means → |
| Gson Java 21.0.12 | accepted — no error |
| Gson JsonParser (lenient off) Java 21.0.12 | accepted — no error |
| hjson Node.js 22.22.2 | End of input while parsing an object (missing '}') at line 1,12 >>>"a": hello} ...what this message means → |
| Jackson ObjectMapper Java 21.0.12 | Unrecognized token 'hello': was expecting (JSON String, Number, Array, Object or token 'null', 'true' or 'false')what this message means → |
| JavaScriptCore JSON.parse JavaScriptCore (Bun 1.4.1) | JSON Parse error: Unexpected identifier "hello"what this message means → |
| json-bigint Node.js 22.22.2 | Unexpected 'h' |
| JSON5 Node.js 22.22.2 | JSON5: invalid character 'h' at 1:7what this message means → |
| JSON::PP Perl 5.038002 | malformed JSON string, neither array, object, number, string or atom, at character offset 6 (before "hello}")what this message means → |
| json_decode PHP 8.3.6 | Syntax error |
| Newtonsoft.Json JsonConvert Newtonsoft.Json 13.0.3 on .NET 8.0.30 | Unexpected character encountered while parsing value: h. Path 'a', line 1, position 6.what this message means → |
| Newtonsoft.Json JsonTextReader Newtonsoft.Json 13.0.3 on .NET 8.0.30 | Unexpected character encountered while parsing value: h. Path 'a', line 1, position 6.what this message means → |
| orjson CPython 3.12.3 | unexpected character, expected a JSON value: line 1 column 7 (char 6)what this message means → |
| Ruby JSON.parse Ruby 3.2.3 | unexpected token at '{"a": hello}' |
| serde_json::from_str Rust (serde_json 1.x) | expected value at line 1 column 7what this message means → |
| SpiderMonkey JSON.parse SpiderMonkey 115 | JSON.parse: unexpected character at line 1 column 7 of the JSON datawhat this message means → |
| System.Text.Json Deserialize .NET 8.0.30 | 'h' is an invalid start of a value. Path: $ | LineNumber: 0 | BytePositionInLine: 6.what this message means → |
| System.Text.Json JsonDocument .NET 8.0.30 | 'h' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 6.what this message means → |
| ujson CPython 3.12.3 | Expected object or value |
| V8 JSON.parse Node.js 22.22.2 | Unexpected token 'h', "{"a": hello}" is not valid JSONwhat this message means → |
What the specification says
The exact sections that govern this error. Descriptions are our paraphrase; follow the links for the normative text.
| Body | Section |
|---|---|
| IETF | A value must be an object, array, number, string, or one of the three literal names, which the section states must be lowercase. No other literal names are allowed. |
| IETF | A string begins and ends with a quotation mark. Any Unicode character may appear between them except the quotation mark, the reverse solidus, and the control characters U+0000 through U+001F, which the section requires to be escaped. It also fixes the escape set and the \uXXXX form. |
| Ecma International | A value is an object, array, number, string, true, false or null. |
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