संदर्भ
JSON सिंटैक्स संदर्भ
JSON सिंटैक्स (RFC 8259) का पूर्ण संदर्भ जिसमें डेटा प्रकार, व्याकरण नियम, उदाहरण और सामान्य त्रुटियाँ शामिल हैं।
Last updated: 2026-08-28
| category | name | syntax | description |
|---|---|---|---|
| Type | String | "hello world" | Unicode character sequence wrapped in double quotes. Supports escape sequences: \" \\ \/ \b \f \n \r \t \uXXXX |
| Type | Number | 42, -3.14, 1e10, 2.5E-3 | IEEE 754 double-precision float. No leading zeros (except 0 itself), no NaN, no Infinity, no hexadecimal |
| Type | Boolean | true | false | Literal lowercase keywords true or false (not quoted, not capitalized) |
| Type | Null | null | Literal lowercase keyword null representing absence of value (not quoted) |
| Type | Object | {"key": value, ...} | Unordered collection of key-value pairs. Keys must be unique strings. Empty object: {} |
| Type | Array | [value, value, ...] | Ordered sequence of values of any type. Empty array: []. Values can be mixed types |
| Rule | Double quotes only | "key": "value" | Strings and keys must use double quotes. Single quotes are invalid |
| Rule | Quoted keys | {"name": "Alice"} | Object keys must be wrapped in double quotes (unlike JavaScript object literals) |
| Rule | No trailing comma | {"a": 1, "b": 2} | The last element in an object or array must not have a trailing comma |
| Rule | Root structure | {...} or [...] | Top-level value must be an object or array (per RFC 8259, any value is valid, but many parsers require object/array) |
| Rule | No comments | N/A | JSON does not support // or /* */ comments (unlike JSON5 or JavaScript) |
| Rule | Escape sequences | "line1\nline2" | Use backslash to escape: \" \\ \/ \b \f \n \r \t \uXXXX (4 hex digits) |
| Rule | Unique keys | {"a": 1, "b": 2} | Object keys should be unique. Duplicate keys produce undefined behavior (last wins in most parsers) |
| Rule | Number format | -?[0-9]+(.[0-9]+)?([eE][+-]?[0-9]+)? | Optional minus, integer part, optional fraction, optional exponent. No leading zeros, no + sign, no hex |
| Example | Simple object | {"name": "Alice", "age": 30, "active": true} | A person object with string, number, and boolean values |
| Example | Nested structure | {"user": {"id": 1}, "tags": ["a", "b"]} | Object containing nested object and array |
| Example | Array of objects | [{"id": 1}, {"id": 2}] | Array containing multiple objects (common in API responses) |
| Example | Mixed array | [1, "two", true, null, [5]] | Array with mixed types: number, string, boolean, null, nested array |
| Example | Empty values | {}, [], "" | Empty object, empty array, and empty string are all valid JSON values |
| Error | Single quotes | {'key': 'value'} | INVALID: JSON requires double quotes for strings and keys |
| Error | Trailing comma | {"a": 1, "b": 2,} | INVALID: Trailing comma after the last element is not allowed |
| Error | Unquoted keys | {name: "Alice"} | INVALID: Object keys must be wrapped in double quotes |
| Error | Comments | {/* comment */ "a": 1} | INVALID: JSON does not support comments of any style |
| Error | NaN / Infinity | {"value": NaN} | INVALID: NaN, Infinity, and -Infinity are not valid JSON numbers |
| Error | Leading zeros | {"value": 007} | INVALID: Numbers cannot have leading zeros (use 7, not 007) |
| Error | Undefined | {"value": undefined} | INVALID: undefined is not a JSON value (use null for absence) |
| Error | Hex numbers | {"value": 0xFF} | INVALID: Hexadecimal literals are not supported (use decimal 255) |
| Error | Missing quotes | {name: Alice} | INVALID: Both keys and string values require double quotes |