How to measure elapsed time in Python? How to measure elapsed time in Python? python python

How to measure elapsed time in Python?


If you just want to measure the elapsed wall-clock time between two points, you could use time.time():

import timestart = time.time()print("hello")end = time.time()print(end - start)

This gives the execution time in seconds.

Another option since 3.3 might be to use perf_counter or process_time, depending on your requirements. Before 3.3 it was recommended to use time.clock (thanks Amber). However, it is currently deprecated:

On Unix, return the current processor time as a floating point number expressed in seconds. The precision, and in fact the very definition of the meaning of “processor time”, depends on that of the C function of the same name.

On Windows, this function returns wall-clock seconds elapsed since the first call to this function, as a floating point number, based on the Win32 function QueryPerformanceCounter(). The resolution is typically better than one microsecond.

Deprecated since version 3.3: The behaviour of this function depends on the platform: use perf_counter() or process_time() instead, depending on your requirements, to have a well defined behaviour.


Use timeit.default_timer instead of timeit.timeit. The former provides the best clock available on your platform and version of Python automatically:

from timeit import default_timer as timerstart = timer()# ...end = timer()print(end - start) # Time in seconds, e.g. 5.38091952400282

timeit.default_timer is assigned to time.time() or time.clock() depending on OS. On Python 3.3+ default_timer is time.perf_counter() on all platforms. See Python - time.clock() vs. time.time() - accuracy?

See also:


Python 3 only:

Since time.clock() is deprecated as of Python 3.3, you will want to use time.perf_counter() for system-wide timing, or time.process_time() for process-wide timing, just the way you used to use time.clock():

import timet = time.process_time()#do some stuffelapsed_time = time.process_time() - t

The new function process_time will not include time elapsed during sleep.


matomo