# std::numeric_limits<T>::max_exponent

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< cpp‎ | types‎ | numeric limits

static const int max_exponent; |  | (until C++11)
static constexpr int max_exponent; |  | (since C++11)

The value of std::numeric_limits<T>::max_exponent is the largest positive number n such that \(\scriptsize r^{n-1}\)rn-1
, where r is std::numeric_limits<T>::radix, is a representable finite value of the floating-point type `T`.

### Standard specializations

`T` | value of std::numeric_limits<T>::max_exponent
/* non-specialized */ | ​0​
bool | ​0​
char | ​0​
signed char | ​0​
unsigned char | ​0​
wchar_t | ​0​
char8_t (since C++20) | ​0​
char16_t (since C++11) | ​0​
char32_t (since C++11) | ​0​
short | ​0​
unsigned short | ​0​
int | ​0​
unsigned int | ​0​
long | ​0​
unsigned long | ​0​
long long (since C++11) | ​0​
unsigned long long (since C++11) | ​0​
float | FLT_MAX_EXP
double | DBL_MAX_EXP
long double | LDBL_MAX_EXP

### Example

Demonstrates the relationships of `max_exponent`, max_exponent10, and max() for the type float:

Run this code

    #include <iostream>
    #include <limits>

    int main()
    {
        std::cout << "max() = " << std::numeric_limits<float>::max() << '\n'
                  << "max_exponent10 = " << std::numeric_limits<float>::max_exponent10 << '\n'
                  << std::hexfloat << '\n'
                  << "max() = " << std::numeric_limits<float>::max() << '\n'
                  << "max_exponent = " << std::numeric_limits<float>::max_exponent << '\n';
    }

Output:

    max() = 3.40282e+38
    max_exponent10 = 38

    max() = 0x1.fffffep+127
    max_exponent = 128

### See also

min_exponent10 [static] | the smallest negative power of ten that is a valid normalized floating-point value (public static member constant)
min_exponent [static] | one more than the smallest negative power of the radix that is a valid normalized floating-point value (public static member constant)
max_exponent10 [static] | the largest integer power of 10 that is a valid finite floating-point value (public static member constant)

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