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

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"^ ([\w-_ ]+):\n\n +Type: AirPort\n +Hardware.+\n +BSD Device Name: (.+)\n +IPv4 Addresses: (192[\.\d]+)$" test_str = ("ETHERNET DISCONNECTED, WI-FI RUNNING\n" "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n\n\n\n" "Network:\n\n" " Thunderbolt Ethernet Slot 1:\n\n" " Type: Ethernet\n" " Hardware: Ethernet\n" " BSD Device Name: en8\n" " IPv4:\n" " Configuration Method: DHCP\n" " IPv6:\n" " Configuration Method: Automatic\n" " Ethernet:\n" " MAC Address: 00:50:b6:ca:f0:dc\n" " Media Options: \n" " Media Subtype: Auto Select\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 0\n\n" " Thunderbolt Ethernet:\n\n" " Type: Ethernet\n" " Hardware: Ethernet\n" " BSD Device Name: en6\n" " IPv4:\n" " Configuration Method: DHCP\n" " IPv6:\n" " Configuration Method: Automatic\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 1\n\n" " Wi-Fi:\n\n" " Type: AirPort\n" " Hardware: AirPort\n" " BSD Device Name: en0\n" " IPv4 Addresses: 192.168.1.16\n" " IPv4:\n" " AdditionalRoutes:\n" " DestinationAddress: 192.168.1.16\n" " SubnetMask: 255.255.255.255\n" " DestinationAddress: 169.254.0.0\n" " SubnetMask: 255.255.0.0\n" " Addresses: 192.168.1.16\n" " ARPResolvedHardwareAddress: 2c:b0:5d:25:af:69\n" " ARPResolvedIPAddress: 192.168.1.1\n" " Configuration Method: DHCP\n" " ConfirmedInterfaceName: en0\n" " Interface Name: en0\n" " Network Signature: IPv4.Router=192.168.1.1;IPv4.RouterHardwareAddress=2c:b0:5d:25:af:69\n" " Router: 192.168.1.1\n" " Subnet Masks: 255.255.255.0\n" " IPv6:\n" " Configuration Method: Automatic\n" " DNS:\n" " Server Addresses: 192.168.1.1\n" " DHCP Server Responses:\n" " Domain Name Servers: 192.168.1.1\n" " Lease Duration (seconds): 0\n" " DHCP Message Type: 0x05\n" " Routers: 192.168.1.1\n" " Server Identifier: 192.168.1.1\n" " Subnet Mask: 255.255.255.0\n" " Ethernet:\n" " MAC Address: 28:cf:e9:17:e0:d1\n" " Media Options: \n" " Media Subtype: Auto Select\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 2\n\n" " USB Ethernet:\n\n" " Type: Ethernet\n" " Hardware: Ethernet\n" " BSD Device Name: en3\n" " IPv4:\n" " Configuration Method: DHCP\n" " IPv6:\n" " Configuration Method: Automatic\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 3\n\n" " AX88179 USB 3.0 to Gigabit Ethernet:\n\n" " Type: Ethernet\n" " Hardware: Ethernet\n" " BSD Device Name: en7\n" " IPv4:\n" " Configuration Method: DHCP\n" " IPv6:\n" " Configuration Method: Automatic\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 4\n\n" " Thunderbolt FireWire:\n\n" " Type: FireWire\n" " Hardware: FireWire\n" " BSD Device Name: fw0\n" " IPv4:\n" " Configuration Method: DHCP\n" " IPv6:\n" " Configuration Method: Automatic\n" " Ethernet:\n" " MAC Address: 00:50:b6:10:00:00:5d:31\n" " Media Options: Full Duplex\n" " Media Subtype: Auto Select\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 5\n\n" " iPhone:\n\n" " Type: Ethernet\n" " Hardware: Ethernet\n" " BSD Device Name: en5\n" " IPv4:\n" " Configuration Method: DHCP\n" " IPv6:\n" " Configuration Method: Automatic\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 6\n\n" " Bluetooth PAN:\n\n" " Type: Ethernet\n" " Hardware: Ethernet\n" " BSD Device Name: en4\n" " IPv4:\n" " Configuration Method: DHCP\n" " IPv6:\n" " Configuration Method: Automatic\n" " Proxies:\n" " Exceptions List: *.local, 169.254/16\n" " FTP Passive Mode: Yes\n" " Service Order: 7\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