Python – Measure time taken by program to execute

This article aims to show how to measure the time taken by the program to execute. Calculating time helps to optimize your Python script to perform better. 

Approach #1 : 

A simple solution to it is to use time module to get the current time. The following steps calculate the running time of a program or section of a program.

• Store the starting time before the first line of the program executes.
• Store the ending time after the last line of the program executes.
• Print the difference between start time and end time.

Code #1 : 

Python3

# Code to Measure time taken by program to execute.
import time

# store starting time
begin = time.time()

# program body starts

for i in range(5):
    print("GeeksForGeeks")
# program body ends

time.sleep(1)
# store end time
end = time.time()

# total time taken
print(f"Total runtime of the program is {end - begin}")

Output

GeeksForGeeks
GeeksForGeeks
GeeksForGeeks
GeeksForGeeks
GeeksForGeeks
Total runtime of the program is 1.0009586811065674

Time Complexity: O(1)
Auxiliary Space: O(1)

Approach #2 : Using Timeit module 

Python3

# importing the required module
import timeit

# code snippet to be executed only once
mysetup = "from math import sqrt"

# code snippet whose execution time is to be measured
mycode = '''
def example():
    mylist = []
    for x in range(100):
        mylist.append(sqrt(x))
'''

# timeit statement
print timeit.timeit(setup = mysetup, stmt = mycode, number = 10000)

Output: 

0.00119590759277

 Approach #3 : Using default_timer() method in timeit module 

Python3

import timeit

startTime = timeit.default_timer()

for _ in range(100):
    statement = "GeeksForGeeks"

endTime = timeit.default_timer()

print(endTime - startTime)

Output

1.2153992429375648e-05

Approach #4 : Using the datetime module

Python3

import datetime

startTime = datetime.datetime.now()

for _ in range(1_00_00_000):
    statement = "GeeksForGeeks"

endTime = datetime.datetime.now()

print(endTime - startTime)

Output

0:00:00.588817

Note: Output may vary depending on the system or server load. To read more about Timeit modulule, refer – Timeit in Python with Examples