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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\d{44}" test_str = (" Found 55 barcodes:\n" " 1) I2of5, Confidence: 1,00, Page 1, Rectangle: [231; 2494; 1271; 1]\n" " Value: 89620000002429000411110202208291001225388559\n" " 2) I2of5, Confidence: 0,50, Page 2, Rectangle: [606; 645; 219; 1]\n" " Value: 3505\n" " 3) I2of5, Confidence: 1,00, Page 2, Rectangle: [266; 2478; 1270; 1]\n" " Value: 89650000002409000411110202207291001225323761\n" " 4) I2of5, Confidence: 0,50, Page 3, Rectangle: [2058; 1985; 192; 1]\n" " Value: 5862\n" " 5) I2of5, Confidence: 0,50, Page 3, Rectangle: [260; 2485; 1270; 1]\n" " Value: 89680000002429000411110202208291001225388504\n" " 6) I2of5, Confidence: 0,50, Page 4, Rectangle: [1544; 1229; 280; 1]\n" " Value: 0316\n" " 7) I2of5, Confidence: 0,50, Page 4, Rectangle: [279; 2487; 1271; 1]\n" " Value: 89620000002429000411110202208291001225388502\n" " 8) I2of5, Confidence: 1,00, Page 5, Rectangle: [258; 2491; 1271; 1]\n" " Value: 89610000002429000411110202208291001225388499\n" " 9) I2of5, Confidence: 0,50, Page 6, Rectangle: [237; 2601; 1271; 1]\n" " Value: 89660000002553300411110202208291001225310933\n" " 10) I2of5, Confidence: 0,50, Page 7, Rectangle: [575; 1557; 220; 1]\n" " Value: 1555\n" " 11) I2of5, Confidence: 0,50, Page 7, Rectangle: [239; 2508; 1270; 1]\n" " Value: 89670000002429000411110202208291001225388552\n" " 12) I2of5, Confidence: 0,50, Page 8, Rectangle: [254; 2413; 1270; 1]\n" " Value: 89650000002429000411110202208291001225388497\n" " 13) I2of5, Confidence: 0,50, Page 9, Rectangle: [584; 1563; 226; 1]\n" " Value: 1545\n" " 14) I2of5, Confidence: 0,50, Page 9, Rectangle: [237; 2515; 1271; 1]\n" " Value: 89610000002429000411110202208291001225388480\n" " 15) I2of5, Confidence: 0,50, Page 10, Rectangle: [575; 655; 228; 1]\n" " Value: 2555\n" " 16) I2of5, Confidence: 0,50, Page 10, Rectangle: [578; 1553; 226; 1]\n" " Value: 1555\n" " 17) I2of5, Confidence: 1,00, Page 10, Rectangle: [236; 2497; 1270; 1]\n" " Value: 89620000002429000411110202208291001225388540\n" " 18) I2of5, Confidence: 0,50, Page 11, Rectangle: [231; 2475; 1266; 1]\n" " Value: 89680000003888000411110202208191001225366638\n" " 19) I2of5, Confidence: 0,50, Page 12, Rectangle: [231; 2473; 1266; 1]\n" " Value: 89680000003888000411110202208191001225366662\n" " 20) I2of5, Confidence: 0,50, Page 13, Rectangle: [1517; 364; 280; 1]\n" " Value: 0316\n" " 21) I2of5, Confidence: 0,50, Page 13, Rectangle: [619; 614; 319; 1]\n" " Value: 797113\n" " 22) I2of5, Confidence: 0,50, Page 13, Rectangle: [264; 2539; 1265; 1]\n" " Value: 89600000002429000411110202208261001225388255\n" " 23) I2of5, Confidence: 1,00, Page 14, Rectangle: [228; 2523; 641; 1]\n" " Value: 8968000000281200041111\n" " 24) I2of5, Confidence: 1,00, Page 14, Rectangle: [228; 2526; 815; 1]\n" " Value: 8968000000281200041111020220\n" " 25) I2of5, Confidence: 0,50, Page 14, Rectangle: [228; 2533; 1214; 1]\n" " Value: 896800000028120004111102022082610012253881\n" " 26) I2of5, Confidence: 0,50, Page 14, Rectangle: [228; 2535; 1263; 1]\n" " Value: 89680000002812000411110202208261001225388113\n" " 27) I2of5, Confidence: 0,50, Page 15, Rectangle: [275; 2539; 1264; 1]\n" " Value: 89660000002429000411110202208261001225388115\n" " 28) I2of5, Confidence: 1,00, Page 16, Rectangle: [249; 2454; 1263; 1]\n" " Value: 89610000002429000411110202208291001225388512\n" " 29) I2of5, Confidence: 0,50, Page 17, Rectangle: [581; 679; 228; 1]\n" " Value: 2505\n" " 30) I2of5, Confidence: 1,00, Page 17, Rectangle: [581; 1548; 209; 1]\n" " Value: 3759\n" " 31) I2of5, Confidence: 0,50, Page 17, Rectangle: [240; 2622; 1263; 1]\n" " Value: 89600000000971600411110202208291001225388554\n" " 32) I2of5, Confidence: 0,50, Page 18, Rectangle: [1502; 1192; 279; 1]\n" " Value: 0316\n" " 33) I2of5, Confidence: 1,00, Page 18, Rectangle: [243; 2376; 1263; 1]\n" " Value: 89610000003037000411110202208291001225388574\n" " 34) I2of5, Confidence: 0,50, Page 19, Rectangle: [1484; 1229; 279; 1]\n" " Value: 0316\n" " 35) I2of5, Confidence: 0,50, Page 19, Rectangle: [224; 2454; 1263; 1]\n" " Value: 89690000002429000411110202208291001225388773\n" " 36) I2of5, Confidence: 0,50, Page 20, Rectangle: [276; 2536; 1262; 1]\n" " Value: 89650000002429000411110202208291001225388812\n" " 37) I2of5, Confidence: 0,50, Page 21, Rectangle: [590; 1578; 225; 1]\n" " Value: 2505\n" " 38) I2of5, Confidence: 0,50, Page 21, Rectangle: [242; 2566; 1263; 1]\n" " Value: 89600000002510000411110202208291001225388894\n" " 39) I2of5, Confidence: 0,50, Page 22, Rectangle: [576; 1500; 228; 1]\n" " Value: 1505\n" " 40) I2of5, Confidence: 0,50, Page 22, Rectangle: [234; 2451; 1263; 1]\n" " Value: 89620000002429000411110202208291001225388936\n" " 41) I2of5, Confidence: 1,00, Page 23, Rectangle: [224; 2457; 1263; 1]\n" " Value: 89610000002892000411110202208291001225388743\n" " 42) I2of5, Confidence: 0,50, Page 24, Rectangle: [575; 670; 225; 1]\n" " Value: 3505\n" " 43) I2of5, Confidence: 0,50, Page 24, Rectangle: [573; 1578; 225; 1]\n" " Value: 3595\n" " 44) I2of5, Confidence: 0,50, Page 24, Rectangle: [230; 2533; 1263; 1]\n" " Value: 89630000002579000411110202208291001225388890\n" " 45) I2of5, Confidence: 0,50, Page 25, Rectangle: [584; 1583; 223; 1]\n" " Value: 2545\n" " 46) I2of5, Confidence: 0,50, Page 25, Rectangle: [240; 2536; 1263; 1]\n" " Value: 89660000002429000411110202208291001225389825\n" " 47) I2of5, Confidence: 0,50, Page 26, Rectangle: [240; 2539; 1265; 1]\n" " Value: 89610000002429000411110202208291001225389941\n" " 48) I2of5, Confidence: 1,00, Page 27, Rectangle: [1814; 312; 226; 1]\n" " Value: 829571\n" " 49) I2of5, Confidence: 0,50, Page 27, Rectangle: [231; 2382; 1263; 1]\n" " Value: 89640000003037000411110202208291001225388431\n" " 50) I2of5, Confidence: 0,50, Page 28, Rectangle: [231; 2533; 1263; 1]\n" " Value: 89660000003037000411110202208291001225388307\n" " 51) I2of5, Confidence: 0,50, Page 29, Rectangle: [582; 1349; 159; 1]\n" " Value: 4416\n" " 52) I2of5, Confidence: 0,50, Page 29, Rectangle: [237; 2455; 1265; 1]\n" " Value: 89670000003037000411110202208291001225390079\n" " 53) I2of5, Confidence: 0,50, Page 30, Rectangle: [1932; 528; 140; 1]\n" " Value: 0884\n" " 54) I2of5, Confidence: 0,50, Page 30, Rectangle: [269; 552; 136; 1]\n" " Value: 8222\n" " 55) I2of5, Confidence: 0,50, Page 30, Rectangle: [231; 2527; 1265; 1]\n" " Value: 89670000003012000411110202208291001225390108\n\n" " Decoding took: 1,705 seconds.\n" " Preparations: 1,232 seconds.\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # 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