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
Processing...

Test String

Code Generator

Generated Code

import re regex = re.compile(r"\{\"app_id\":\"(?P<appid>(?:\w+))\",\"dev_id\":\"(?P<devid>(?:\w+))\",\"hardware_serial\":\"(?P<hardwareserial>(?:\w+))\",\"port\":(?P<port>(?:\d+)),\"counter\":(?P<counter>(?:\d+)),\"payload_raw\":\"(?P<raw>(?:(\w+\=|\w+|\w+\==)))\",\"payload_fields\":{\"(?P<value>(?:\w+))\":\"(?P<val>(?:\d+))\"},\"metadata\":{\"time\":\"(?P<time>(?:\w+-\w+-\w+:\w+:\w+.\w+))\",\"frequency\":(?P<freq>(?:(\w+.*\w+|\d+))),\"modulation\":\"(?P<modulation>(?:\w+))\",\"data_rate\":\"(?P<data_rate>(?:\w+))\",\"airtime\":(?P<airtime>(?:\w+)),\"coding_rate\":\"(?P<coding_rate>(?:\d+\/\w+))\",\"gateways\":\[{\"gtw_id\":\"(?P<gtw_id>(?:(\w+|\w+\-\w+)))\"(|,\"gtw_trusted\":(?P<trusted>(?:\w+))),\"timestamp\":(?P<timestamp>(?:\w+)),\"time\":\"(?P<times>(?:(\w+.\w+.\w+.\w+.\w+|\w+.\w+.\w+.\w+.\w+.\w+)))\",\"channel\":(?P<channel>(?:\d+)),\"rssi\":-(?P<rssi>(?:\d+)),\"snr\":(?P<snr>(?:(\d+.\d+|\d+))),\"rf_chain\":(?P<rf_chain>(?:\d+)),\"latitude\":(?P<latitude>(?:(\d+.\d+|\d+))),\"longitude\":(?P<longitude>(?:\b(\d*.\d+|\d)\b)),\"location_source\":\"(?P<registry>(?:\w+))\"}\]}}", flags=re.MULTILINE) test_str = "" matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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