Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(.+ Muffin)" test_str = ("Raspberry Muffin\n" "Raspberry \n" "Raisin Muffin\n" "Muffin\n" "Wings\n" "Soup\n" "Toast\n" "Tater Tots\n" "Tatted Tots\n" "Tatter Tots\n" "Shake\n" "Salami\n" "Salmon\n" "Hash Browns\n" "Quinoa\n" "Raspberry Muffin\n" "Bud Light\n" "Coke Zero\n" "Diet Coke\n" "French Onion Soup\n" "Tacos\n" "Turkey\n" "What time is it\n" "Cranberries\n" "Yogurt\n" "YT\n" "Peas\n" "Chocolate\n" "Pancakes\n" "Lime\n" "Hot Dog\n" "French Fried\n" "Egg\n" "Sashimi\n" "Cherrios\n" "Buzzy\n" "Carrot \n" "Coke\n" "Granola\n" "Hi \n" "Gum\n" "test\n" "Hamburger\n" "Lol\n" "Meat\n" "foot\n" "Omelet\n" "Pretzels\n" "Siracha hot sauce\n" "Strawberry smoothie\n" "What now?\n" "Cheerios\n" "pretzel\n" "Doctor Pepper\n" "Root Beer\n" "diet root beer\n" "Orange\n" "Canola\n" "Plum\n" "Spaghetti\n" "Sushi\n" "Agave\n" "Agave syrup\n" "Alcohol\n" "Almond\n" "Almonds\n" "Apple\n" "Apples\n" "Apples\n" "Artichoke\n" "Asparagus\n" "Are these okay?\n" "Are these ok?\n" "Avocado\n" "Avocado oil\n" "badlist\n" "Bacon\n" "Bananas\n" "Beans\n" "Beans / Legumes\n" "Beef\n" "Beet sugar\n" "Beets\n" "Blackberries\n" "Blueberries\n" "Brazil nuts\n" "bread\n" "Broccoli\n" "Brussels sprouts\n" "Butter\n" "Cabbage\n" "Candied nuts\n" "Can\n" "candy\n" "Canola oil\n" "Carrots\n" "Cashew\n" "Cashews\n" "Cashews\n" "Cauliflower\n" "Celery\n" "Celery root\n" "cereal\n" "Cheese\n" "Cheetos\n" "Cherries\n" "Chia and Flax seeds\n" "Chicken\n" "Chickpeas\n" "coconut sugar\n" "Coffee\n" "Corn\n" "Corn oil\n" "Crab\n" "Cream\n" "Cream cheese\n" "Cucumber\n" "Diet coke\n" "diet soda\n" "Eggplant\n" "Eggs\n" "Fish\n" "French fries\n" "Fried chicken\n" "Frozen yogurt\n" "Fruit\n" "Ghee\n" "Gin\n" "grains\n" "Green onions\n" "Green peas\n" "Greens (spinach, kale, etc.)\n" "Guacamole\n" "Herbs (parsley, basil, etc.)\n" "Honeyed nuts\n" "Ice cream\n" "Jerky\n" "kale\n" "ketchup\n" "Lamb\n" "Lard\n" "Lettuce\n" "Lima beans\n" "Lobster\n" "Macadamias\n" "Mango\n" "Mayo\n" "Mayonnaise\n" "Meatballs\n" "Meatloaf\n" "meatloaf\n" "Melon\n" "Milk\n" "Milky Way\n" "Mushrooms\n" "Mussels\n" "Nuts\n" "Olive oil\n" "Olives\n" "Onions\n" "Oranges\n" "Oysters\n" "Palm sugar\n" "Parsnips\n" "pasta\n" "Peach\n" "Pears\n" "Pecans\n" "Peppers\n" "pizza\n" "Plantains\n" "Plums\n" "Popcorn\n" "Popsicle\n" "Pork\n" "potato\n" "Potatoes\n" "poultry\n" "Pumpkin\n" "Raspberries\n" "Rice\n" "Rum\n" "Shrimp\n" "Snack mix\n" "Soda\n" "Soybean oil\n" "Steak\n" "Stevia\n" "Strawberries\n" "Sugar\n" "Sugar-free soda\n" "Sugared nuts\n" "Sunflower seeds\n" "Sweet potatoes and yams\n" "Tallow\n" "Tea\n" "Tomatoes\n" "tomatoes\n" "Trail mix\n" "Vegetable oil\n" "Vodka\n" "Walnuts\n" "Water\n" "What can I say\n" "Whiskey\n" "whole grain bread\n" "Whole Milk\n" "why\n" "wine\n" "Winter squash\n" "Xylitol\n" "Yogurt-covered nuts\n" "Zucchini\n" "zzz") subst = "$1" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html