A Quick Guide to Python String Methods with Examples

Introduction

Python strings come with numerous built-in methods to manipulate text efficiently. Below is a quick guide to all the key string methods with brief explanations and examples.

1. capitalize()

Converts the first character to uppercase.

"text".capitalize()  # 'Text'

2. casefold()

Converts string to lowercase (more aggressive than lower()).

"TeXt".casefold()  # 'text'

3. center(width, fillchar)

Centers the string with specified width and optional fill character.

"text".center(10, '-')  # '--text---'

4. count(substring, start, end)

Counts occurrences of a substring in the string.

"hello".count('l')  # 2

5. encode(encoding, errors)

Encodes the string using the specified encoding.

"text".encode('utf-8')  # b'text'

6. endswith(suffix, start, end)

Checks if the string ends with the specified suffix.

"text".endswith('xt')  # True

7. expandtabs(tabsize)

Replaces tabs with spaces.

"1\t2\t3".expandtabs(4)  # '1   2   3'

8. find(substring, start, end)

Finds the index of the first occurrence of a substring.

"hello".find('e')  # 1

9. format(*args, **kwargs)

Formats a string with placeholders.

"Hello, {}".format("world")  # 'Hello, world'

10. format_map(mapping)

Formats a string using a dictionary.

"{name}".format_map({"name": "John"})  # 'John'

11. index(substring, start, end)

Finds the index of the first occurrence (raises error if not found).

"hello".index('l')  # 2

12. isalnum()

Checks if all characters are alphanumeric.

"text123".isalnum()  # True

13. isalpha()

Checks if all characters are alphabetic.

"text".isalpha()  # True

14. isdecimal()

Checks if all characters are decimal digits.

"123".isdecimal()  # True

15. isdigit()

Checks if all characters are digits.

"123".isdigit()  # True

16. islower()

Checks if all characters are lowercase.

"text".islower()  # True

17. isnumeric()

Checks if all characters are numeric.

"123".isnumeric()  # True

18. isspace()

Checks if all characters are whitespace.

"   ".isspace()  # True

19. istitle()

Checks if the string is title-cased.

"Hello World".istitle()  # True

20. isupper()

Checks if all characters are uppercase.

"TEXT".isupper()  # True

21. join(iterable)

Joins elements of an iterable with a string separator.

",".join(["a", "b", "c"])  # 'a,b,c'

22. ljust(width, fillchar)

Left-aligns the string with specified width.

"text".ljust(10, '-')  # 'text------'

23. lower()

Converts all characters to lowercase.

"TEXT".lower()  # 'text'

24. lstrip(chars)

Removes leading characters.

"   text".lstrip()  # 'text'

25. maketrans(x, y, z)

Creates a translation table for translate().

str.maketrans("abc", "123")  # mapping table

26. partition(separator)

Splits the string at the first occurrence of separator.

"text_partition".partition('_')  # ('text', '_', 'partition')

27. replace(old, new, count)

Replaces occurrences of a substring.

"hello".replace("l", "x")  # 'hexxo'

28. rfind(substring, start, end)

Finds the last occurrence of a substring.

"hello".rfind('l')  # 3

29. rindex(substring, start, end)

Finds the last occurrence (raises error if not found).

"hello".rindex('l')  # 3

30. rjust(width, fillchar)

Right-aligns the string with specified width.

"text".rjust(10, '-')  # '------text'

31. rpartition(separator)

Splits the string at the last occurrence of the separator.

"text_rpartition".rpartition('_')  # ('text', '_', 'rpartition')

32. rsplit(separator, maxsplit)

Splits the string from the right.

"1,2,3".rsplit(',', 1)  # ['1,2', '3']

33. rstrip(chars)

Removes trailing characters.

"text   ".rstrip()  # 'text'

34. split(separator, maxsplit)

Splits a string into a list.

"1,2,3".split(',')  # ['1', '2', '3']

35. splitlines(keepends)

Splits by line breaks.

"hello\nworld".splitlines()  # ['hello', 'world']

36. startswith(prefix, start, end)

Checks if the string starts with the specified prefix.

"text".startswith('t')  # True

37. strip(chars)

Removes leading and trailing characters.

"   text   ".strip()  # 'text'

38. swapcase()

Swaps the case of all characters.

"Hello".swapcase()  # 'hELLO'

39. title()

Converts the string to title case.

"hello world".title()  # 'Hello World'

40. translate(table)

Translates the string using a translation table.

"text".translate(str.maketrans("t", "T"))  # 'TexT'

41. upper()

Converts all characters to uppercase.

"text".upper()  # 'TEXT'

42. zfill(width)

Pads the string with zeros on the left.

"42".zfill(5)  # '00042'

Conclusion

Python’s string methods allow for efficient and readable text manipulation. Whether you're formatting, splitting, or modifying text, these methods cover nearly every scenario you’ll encounter in string processing.