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1# basic_json::max_size
2
3```cpp
4size_type max_size() const noexcept;
5```
6
7Returns the maximum number of elements a JSON value is able to hold due to system or library implementation limitations,
8i.e. `std::distance(begin(), end())` for the JSON value.
9
10## Return value
11
12The return value depends on the different types and is defined as follows:
13
14Value type  | return value
15----------- | -------------
16null        | `0` (same as [`size()`](size.md))
17boolean     | `1` (same as [`size()`](size.md))
18string      | `1` (same as [`size()`](size.md))
19number      | `1` (same as [`size()`](size.md))
20binary      | `1` (same as [`size()`](size.md))
21object      | result of function `object_t::max_size()`
22array       | result of function `array_t::max_size()`
23
24## Exception safety
25
26No-throw guarantee: this function never throws exceptions.
27
28## Complexity
29
30Constant, as long as [`array_t`](array_t.md) and [`object_t`](object_t.md) satisfy the
31[Container](https://en.cppreference.com/w/cpp/named_req/Container) concept; that is, their `max_size()` functions have
32constant complexity.
33
34## Notes
35
36This function does not return the maximal length of a string stored as JSON value -- it returns the maximal number of
37string elements the JSON value can store which is `1`.
38
39## Example
40
41??? example
42
43    The following code calls `max_size()` on the different value types. Note the output is implementation specific.
44
45    ```cpp
46    --8<-- "examples/max_size.cpp"
47    ```
48
49    Output:
50
51    ```json
52    --8<-- "examples/max_size.output"
53    ```
54
55## Version history
56
57- Added in version 1.0.0.
58- Extended to return `1` for binary types in version 3.8.0.
59