Defined in header <chrono>
    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).

(until C++23)

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

constructs a new time point
(public member function)
returns the time point as duration since the start of its clock
(public member function)
modifies the time point by the given duration
(public member function)
increments or decrements the duration
(public member function)
returns the time point corresponding to the smallest duration
(public static member function)
returns the time point corresponding to the largest duration
(public static member function)

Non-member functions

performs add and subtract operations involving a time point
(function template)
(C++11)(C++11)(removed in C++20)(C++11)(C++11)(C++11)(C++11)(C++20)
compares two time points
(function template)
converts a time point to another time point on the same clock, with a different duration
(function template)
converts a time_point to another, rounding down
(function template)
converts a time_point to another, rounding up
(function template)
converts a time_point to another, rounding to nearest, ties to even
(function template)

Helper classes

specializes the std::common_type trait
(class template specialization)


#include <algorithm>
#include <chrono>
#include <ctime>
#include <iomanip>
#include <iostream>
void slow_motion()
    static int a[] {1,2,3,4,5,6,7,8,9,10,11,12};
    // Generate Γ(13) == 12! permutations:
    while (std::ranges::next_permutation(a).found) { }
int main()
    using namespace std::literals; // enables the usage of 24h, 1ms, 1s instead of
                                   // e.g. std::chrono::hours(24), accordingly
    const std::chrono::time_point<std::chrono::system_clock> now =
    const std::time_t t_c = std::chrono::system_clock::to_time_t(now - 24h);
    std::cout << "24 hours ago, the time was "
              << std::put_time(std::localtime(&t_c), "%F %T.\n") << std::flush;
    const std::chrono::time_point<std::chrono::steady_clock> start =
    std::cout << "Different clocks are not comparable: \n"
                 "  System time: " << now.time_since_epoch() << "\n"
                 "  Steady time: " << start.time_since_epoch() << '\n';
    const auto end = std::chrono::steady_clock::now();
        << "Slow calculations took "
        << std::chrono::duration_cast<std::chrono::microseconds>(end - start) << " ≈ "
        << (end - start) / 1ms << "ms ≈ " // almost equivalent form of the above, but
        << (end - start) / 1s << "s.\n";  // using milliseconds and seconds accordingly

Possible output:

24 hours ago, the time was 2021-02-15 18:28:52.
Different clocks are not comparable:
  System time: 1666497022681282572ns
  Steady time: 413668317434475ns
Slow calculations took 2090448µs ≈ 2090ms ≈ 2s.

See also

a time interval
(class template)
represents a specific year, month, and day

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