Python:timeit

lastmod 2024-08-02created 2024-08-022 edits

Measure execution time of small code snippets

Basic examples

The following example shows how to use the command-line interface to compare three different expressions:

python -m timeit "'-'.join(str(n) for n in range(100))"
## 10000 loops, best of 5: 30.2 usec per loop

python -m timeit "'-'.join([str(n) for n in range(100)])"
## 10000 loops, best of 5: 27.5 usec per loop

python -m timeit "'-'.join(map(str, range(100)))"
## 10000 loops, best of 5: 23.2 usec per loop

With the Python interface, this can be done as follows:

import timeit

timeit.timeit('"-".join(str(n) for n in range(100))', number=10000)
## 0.3018611848820001

timeit.timeit('"-".join([str(n) for n in range(100)])', number=10000)
## 0.2727368790656328

timeit.timeit('"-".join(map(str, range(100)))', number=10000)
## 0.23702679807320237

A callable can also be passed to the Python interface:

timeit.timeit(lambda: "-".join(map(str, range(100))), number=10000)
## 0.19665591977536678

Note, however, that timeit() automatically determines the number of repetitions only when the command-line interface is used. More advanced examples can be found in the Examples section.

Python:timeit

Basic examples

See also