Skip to main content

Utility functions for strings validation and manipulation.

Project description

Build Status codecov Documentation Status Python 3.5 Python 3.6 Python 3.7 Python 3.8

Python String Utils

Latest version: 1.0.0 (March 2020)

A handy library to validate, manipulate and generate strings, which is:

  • Simple and "pythonic"
  • Fully documented and with examples! (html version on
  • 100% code coverage! (see it with your own eyes on
  • Tested (automatically on each push thanks to Travis CI) against all officially supported Python versions
  • Fast (mostly based on compiled regex)
  • Free from external dependencies
  • PEP8 compliant

What's inside...

Library structure

The library basically consists in the python package string_utils, containing the following modules:

  • (contains string check api)
  • (contains string transformation api)
  • (contains string generation api)
  • (contains library-specific errors)
  • (contains compiled regex FOR INTERNAL USAGE ONLY)

Plus a secondary package tests which includes several submodules.
Specifically one for each test suite and named according to the api to test (eg. tests for is_ip() will be in and so on).

All the public API are importable directly from the main package string_utils, so this:

from string_utils.validation import is_ip

can be simplified as:

from string_utils import is_ip

Api overview

Bear in mind: this is just an overview, for the full API documentation see:

String validation functions:

is_string: checks if the given object is a string

is_string('hello') # returns true
is_string(b'hello') # returns false

is_full_string: checks if the given object is non empty string

is_full_string(None) # returns false
is_full_string('') # returns false
is_full_string(' ') # returns false
is_full_string('foo') # returns true

is_number: checks if the given string represents a valid number

is_number('42') # returns true
is_number('-25.99') # returns true
is_number('1e3') # returns true
is_number(' 1 2 3 ') # returns false

is_integer: checks if the given string represents a valid integer

is_integer('42') # returns true
is_integer('42.0') # returns false

is_decimal: checks if the given string represents a valid decimal number

is_decimal('42.0') # returns true
is_decimal('42') # returns false

is_url: checks if the given string is an url

is_url('') # returns false
is_url('') # returns true
is_url('') # returns true

is_email: Checks if the given string is an email

is_email('') # returns true
is_eamil('') # retruns false

is_credit_card: Checks if the given string is a credit card


# returns true if `value` represents a valid card number for one of these:

is_camel_case: Checks if the given string is formatted as camel case

is_camel_case('MyCamelCase') # returns true
is_camel_case('hello') # returns false

is_snake_case: Checks if the given string is formatted as snake case

is_snake_case('snake_bites') # returns true
is_snake_case('nope') # returns false

is_json: Checks if the given string is a valid json

is_json('{"first_name": "Peter", "last_name": "Parker"}') # returns true
is_json('[1, 2, 3]') # returns true
is_json('{nope}') # returns false

is_uuid: Checks if the given string is a valid UUID

is_uuid('ce2cd4ee-83de-46f6-a054-5ee4ddae1582') # returns true

is_ip_v4: Checks if the given string is a valid ip v4 address

is_ip_v4('') # returns true
is_ip_v4('') # returns false (999 is out of range)

is_ip_v6: Checks if the given string is a valid ip v6 address

is_ip_v6('2001:db8:85a3:0000:0000:8a2e:370:7334') # returns true
is_ip_v6('123:db8:85a3:0000:0000:8a2e:370,1') # returns false

is_ip: Checks if the given string is a valid ip (any version)

is_ip('') # returns true
is_ip('2001:db8:85a3:0000:0000:8a2e:370:7334') # returns true
is_ip('') # returns false
is_ip('123:db8:85a3:0000:0000:8a2e:370,1') # returns false

is_isnb_13: Checks if the given string is a valid ISBN 13

is_isbn_13('9780312498580') # returns true
is_isbn_13('978-0312498580') # returns true
is_isbn_13('978-0312498580', normalize=False) # returns false

is_isbn_10: Checks if the given string is a valid ISBN 10

is_isbn_10('1506715214') # returns true
is_isbn_10('150-6715214') # returns true
is_isbn_10('150-6715214', normalize=False) # returns false

is_isbn: Checks if the given string is a valid ISBN (any version)

is_isbn('9780312498580') # returns true
is_isbn('1506715214') # returns true

is_slug: Checks if the string is a slug (as created by slugify())

is_slug('my-blog-post-title') # returns true
is_slug('My blog post title') # returns false

contains_html: Checks if the strings contains one ore more HTML/XML tag

contains_html('my string is <strong>bold</strong>') # returns true
contains_html('my string is not bold') # returns false

words_count: Returns the number of words contained in the string

words_count('hello world') # returns 2
words_count('one,two,three') # returns 3 (no need for spaces, punctuation is recognized!)

is_palindrome: Checks if the string is a palindrome

is_palindrome('LOL') # returns true
is_palindrome('ROTFL') # returns false

is_pangram: Checks if the string is a pangram

is_pangram('The quick brown fox jumps over the lazy dog') # returns true
is_pangram('hello world') # returns false

is_isogram: Checks if the string is an isogram

is_isogram('dermatoglyphics') # returns true
is_isogram('hello') # returns false

String manipulation:

camel_case_to_snake: Converts a camel case formatted string into a snake case one

camel_case_to_snake('ThisIsACamelStringTest') # returns 'this_is_a_camel_case_string_test'

snake_case_to_camel: Converts a snake case formatted string into a camel case one

snake_case_to_camel('the_snake_is_green') # returns 'TheSnakeIsGreen'

reverse: Returns the string in a reversed order

reverse('hello') # returns 'olleh'

shuffle: Returns the string with its original chars but at randomized positions

shuffle('hello world') # possible output: 'l wodheorll'

strip_html: Removes all the HTML/XML tags found in a string

strip_html('test: <a href="foo/bar">click here</a>') # returns 'test: '
strip_html('test: <a href="foo/bar">click here</a>', keep_tag_content=True) # returns 'test: click here'

prettify: Reformat a string by applying basic grammar and formatting rules

prettify(' unprettified string ,, like this one,will be"prettified" .it\' s awesome! ')
# the ouput will be: 'Unprettified string, like this one, will be "prettified". It\'s awesome!'

asciify: Converts all non-ascii chars contained in a string into the closest possible ascii representation

# returns 'eeuuooaaeynAAACIINOE' (string is deliberately dumb in order to show char conversion)

slugify: Convert a string into a formatted "slug"

slugify('Top 10 Reasons To Love Dogs!!!') # returns: 'top-10-reasons-to-love-dogs'

booleanize: Convert a string into a boolean based on its content

booleanize('true') # returns true
booleanize('YES') # returns true
booleanize('y') # returns true
booleanize('1') # returns true
booelanize('something else') # returns false

strip_margin: Removes left indentation from multi-line strings (inspired by Scala)

        line 1
        line 2
        line 3

line 1
line 2
line 3

compress/decompress: Compress strings into shorted ones that can be restored back to the original one later on

compressed = compress(my_long_string) # shorter string (URL safe base64 encoded)

decompressed = decompress(compressed) # string restored

assert(my_long_string == decompressed) # yep

roman_encode: Encode integers/string into roman numbers

roman_encode(37) # returns 'XXXVII'

roman_decode: Decode roman number into an integer

roman_decode('XXXVII') # returns 37

roman_range: Generator which returns roman numbers on each iteration

for n in roman_range(10): print(n) # prints: I, II, III, IV, V, VI, VII, VIII, IX, X
for n in roman_range(start=7, stop=1, step=-1): print(n) # prints: VII, VI, V, IV, III, II, I

String generations:

uuid: Returns the string representation of a newly created UUID object

uuid() # possible output: 'ce2cd4ee-83de-46f6-a054-5ee4ddae1582'
uuid(as_hex=True) # possible output: 'ce2cd4ee83de46f6a0545ee4ddae1582'

random_string: Creates a string of the specified size with random chars

random_string(9) # possible output: 'K1URtlTu5'

secure_random_hex: Creates an hexadecimal string using a secure strong random generator

# possible ouput: 'd1eedff4033a2e9867c37ded' 
# (len is 24, because 12 represents the number of random bytes generated, which are then converted to hexadecimal value)


pip install python-string-utils

Checking installed version

import string_utils
'1.0.0' # (if '1.0.0' is the installed version)


Full API documentation available on

Support the project!

Do you like this project? Would you like to see it updated more often with new features and improvements? If so, you can make a small donation by clicking the button down below, it would be really appreciated! :)

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

python-string-utils-1.0.0.tar.gz (20.1 kB view hashes)

Uploaded Source

Built Distribution

python_string_utils-1.0.0-py3-none-any.whl (26.3 kB view hashes)

Uploaded Python 3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page