33 Essential Python CLI Tricks You Should Bookmark

Today I compiled 33 useful Python command‑line tricks. Save them for quick reference.

1. Run Python code without a file

You can execute Python commands directly from the terminal without creating a script file:

python -c "print('kiran')"

2. Use Python as a calculator

Run quick calculations from the command line:

python -c "print(5 * 4 + 100)"

3. Debug with the -i flag

Keep the interpreter open after a script finishes to inspect variables:

python -i my_script.py

4. Get help for any module

Show a module’s documentation from the command line:

python -c "help('math')"

5. Measure code execution time

Use the -m timeit module to benchmark snippets:

python -m timeit "y = [x**2 for x in range(2000)]"

6. Quiet interactive mode with -q

Suppress the startup banner:

python -q

7. List all installed modules

Show every package installed in the current environment:

python -m pip list

8. Run a module directly

Execute a module without a script file, e.g., start a simple HTTP server:

python -m http.server

9. Generate a random number

Use the random module inline:

python -c "import random; print(random.randint(1, 1000))"

10. Check the Python version

python --version

11. Activate a virtual environment

source venv/bin/activate

12. Pretty‑print JSON files

python -m json.tool < input.json > output.json

13. Compress files with gzip

python -c "import gzip, shutil; shutil.copyfileobj(open('file.txt','rb'), gzip.open('file.txt.gz','wb'))"

14. Extract ZIP archives

python -m zipfile -e my_file.zip ./output_folder

15. Generate a quick password

python -c "import secrets; print(secrets.token_urlsafe(16))"

16. Check syntax without running code

python -m py_compile my_script.py

17. Count lines in a file

python -c "print(len(open('file.txt').readlines()))"

18. Test for primality

python -c "print(all(101 % i != 0 for i in range(2, int(101**0.5)+1)))"

19. Launch the REPL anywhere

python

20. Read a CSV file

python -c "import csv; print(list(csv.reader(open('my_file.csv'))))"

21. Sort a file alphabetically

python -c "print(sorted(open('my_file.txt').readlines()))"

22. Send a quick HTTP GET request

python -c "import requests; print(requests.get('https://google.com').text)"

23. Monitor a script’s memory usage

python -m tracemalloc my_script.py

24. Show the current time

python -c "import time; print(time.ctime())"

25. Simulate a dice roll

python -c "import random; print(random.randint(1, 6))"

26. Convert Celsius to Fahrenheit

python -c "c=30; print(f'{c}C = {(c * 9/5) + 32}F')"

27. Create a progress bar

python -c "import time; [print(f'\r{i}%', end='') or time.sleep(0.1) for i in range(101)]"

28. Generate a QR code

python -c "import qrcode; qrcode.make('https://google.com').save('qrcode.png')"

29. Send an email

python -c "import smtplib; s = smtplib.SMTP('smtp.gmail.com', 587); s.starttls(); s.login('your_email', 'your_password'); s.sendmail('from', 'to', 'message'); s.quit()"

30. Compute a factorial

python -c "import math; print(math.factorial(5))"

31. Plot a quick chart

python -c "import matplotlib.pyplot as plt; plt.plot([1,2,3],[4,5,6]); plt.show()"

32. Search for files

python -c "import glob; print(glob.glob('*.txt'))"

33. Check network speed

python -c