# std::chrono::time_point

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< cpp‎ | chrono

Defined in header `<chrono>` |  |
template< class Clock, class Duration = typename Clock::duration > class time_point; |  | (since C++11)

Class template `std::chrono::time_point` represents a point in time. It is implemented as if it stores a value of type `Duration` indicating the time interval from the start of the `Clock`'s epoch.

`Clock` must meet the requirements for Clock or be std::chrono::local_t (since C++20).

### Member types

Member type | Definition
`clock` | `Clock`, the clock on which this time point is measured
`duration` | `Duration`, a std::chrono::duration type used to measure the time since epoch
`rep` | `Rep`, an arithmetic type representing the number of ticks of the duration
`period` | `Period`, a std::ratio type representing the tick period of the duration

### Member functions

(constructor) | constructs a new time point (public member function)
time_since_epoch | returns the time point as duration since the start of its clock (public member function)
operator+=operator-= | modifies the time point by the given duration (public member function)
operator++operator++(int)operator--operator--(int) (C++20) | increments or decrements the duration (public member function)
min [static] | returns the time point corresponding to the smallest duration (public static member function)
max [static] | returns the time point corresponding to the largest duration (public static member function)

### Non-member functions

std::common_type<std::chrono::time_point> | specializes the std::common_type trait (class template specialization)
operator+operator- | performs add and subtract operations involving a time point (function template)
operator==operator!=operator<operator<=operator>operator>= | compares two time points (function template)
time_point_cast | converts a time point to another time point on the same clock, with a different duration (function template)
floor(std::chrono::time_point) (C++17) | converts a time_point to another, rounding down (function template)
ceil(std::chrono::time_point) (C++17) | converts a time_point to another, rounding up (function template)
round(std::chrono::time_point) (C++17) | converts a time_point to another, rounding to nearest, ties to even (function template)

### Example

Run this code

    #include <iostream>
    #include <iomanip>
    #include <ctime>
    #include <chrono>

    int main()
    {
        std::chrono::system_clock::time_point now = std::chrono::system_clock::now();
        std::time_t now_c = std::chrono::system_clock::to_time_t(now - std::chrono::hours(24));
        std::cout << "24 hours ago, the time was "
                  << std::put_time(std::localtime(&now_c), "%F %T") << '\n';

        std::chrono::steady_clock::time_point start = std::chrono::steady_clock::now();
        std::cout << "Hello World\n";
        std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now();
        std::cout << "Printing took "
                  << std::chrono::duration_cast<std::chrono::microseconds>(end - start).count()
                  << "us.\n";
    }

Possible output:

    24 hours ago, the time was 2011-10-25 12:00:08
    Hello World
    Printing took 84us.

### See also

duration (C++11) | a time interval (class template)

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