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

const regex = /^ ([\w-_ ]+):\n\n +Type: Ethernet\n +Hardware.+\n +BSD Device Name: (.+)\n +IPv4 Addresses: (192[\.\d]+)$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^ ([\\w-_ ]+):\\n\\n +Type: Ethernet\\n +Hardware.+\\n +BSD Device Name: (.+)\\n +IPv4 Addresses: (192[\\.\\d]+)$', 'gm') const str = `ETHERNET CONNECTED, NO WI-FI ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Below Source Text from Mac Shell Script: system_profiler SPNetworkDataType ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Network: Thunderbolt Ethernet Slot 1: Type: Ethernet Hardware: Ethernet BSD Device Name: en8 IPv4 Addresses: 192.168.1.15 IPv4: AdditionalRoutes: DestinationAddress: 192.168.1.15 SubnetMask: 255.255.255.255 DestinationAddress: 169.254.0.0 SubnetMask: 255.255.0.0 Addresses: 192.168.1.15 ARPResolvedHardwareAddress: 2c:b0:5d:25:af:69 ARPResolvedIPAddress: 192.168.1.1 Configuration Method: DHCP ConfirmedInterfaceName: en8 Interface Name: en8 Network Signature: IPv4.Router=192.168.1.1;IPv4.RouterHardwareAddress=2c:b0:5d:25:af:69 Router: 192.168.1.1 Subnet Masks: 255.255.255.0 IPv6: Configuration Method: Automatic DNS: Server Addresses: 192.168.1.1 DHCP Server Responses: Domain Name Servers: 192.168.1.1 Lease Duration (seconds): 0 DHCP Message Type: 0x05 Routers: 192.168.1.1 Server Identifier: 192.168.1.1 Subnet Mask: 255.255.255.0 Ethernet: MAC Address: 00:50:b6:ca:f0:dc Media Options: Full Duplex, Flow Control Media Subtype: 1000baseT Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Sleep Proxies: 1 Family Room Apple TV: Marginal Power: 60 Metric: 703560 Portability: 35 Total Power: 63 Type: 70 Service Order: 0 Wi-Fi: Type: AirPort Hardware: AirPort BSD Device Name: en0 IPv4 Addresses: 192.168.1.16 IPv4: AdditionalRoutes: DestinationAddress: 192.168.1.16 SubnetMask: 255.255.255.255 DestinationAddress: 169.254.0.0 SubnetMask: 255.255.0.0 Addresses: 192.168.1.16 ARPResolvedHardwareAddress: 2c:b0:5d:25:af:69 ARPResolvedIPAddress: 192.168.1.1 Configuration Method: DHCP ConfirmedInterfaceName: en0 Interface Name: en0 Network Signature: IPv4.Router=192.168.1.1;IPv4.RouterHardwareAddress=2c:b0:5d:25:af:69 Router: 192.168.1.1 Subnet Masks: 255.255.255.0 IPv6: Configuration Method: Automatic DNS: Server Addresses: 192.168.1.1 DHCP Server Responses: Domain Name Servers: 192.168.1.1 Lease Duration (seconds): 0 DHCP Message Type: 0x05 Routers: 192.168.1.1 Server Identifier: 192.168.1.1 Subnet Mask: 255.255.255.0 Ethernet: MAC Address: 28:cf:e9:17:e0:d1 Media Options: Media Subtype: Auto Select Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 2 Thunderbolt Ethernet: Type: Ethernet Hardware: Ethernet BSD Device Name: en6 IPv4: Configuration Method: DHCP IPv6: Configuration Method: Automatic Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 1 Wi-Fi: Type: AirPort Hardware: AirPort BSD Device Name: en0 IPv4: Configuration Method: DHCP IPv6: Configuration Method: Automatic Ethernet: MAC Address: 28:cf:e9:17:e0:d1 Media Options: Media Subtype: Auto Select Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 2 USB Ethernet: Type: Ethernet Hardware: Ethernet BSD Device Name: en3 IPv4: Configuration Method: DHCP IPv6: Configuration Method: Automatic Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 3 AX88179 USB 3.0 to Gigabit Ethernet: Type: Ethernet Hardware: Ethernet BSD Device Name: en7 IPv4: Configuration Method: DHCP IPv6: Configuration Method: Automatic Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 4 Thunderbolt FireWire: Type: FireWire Hardware: FireWire BSD Device Name: fw0 IPv4: Configuration Method: DHCP IPv6: Configuration Method: Automatic Ethernet: MAC Address: 00:50:b6:10:00:00:5d:31 Media Options: Full Duplex Media Subtype: Auto Select Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 5 iPhone: Type: Ethernet Hardware: Ethernet BSD Device Name: en5 IPv4: Configuration Method: DHCP IPv6: Configuration Method: Automatic Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 6 Bluetooth PAN: Type: Ethernet Hardware: Ethernet BSD Device Name: en4 IPv4: Configuration Method: DHCP IPv6: Configuration Method: Automatic Proxies: Exceptions List: *.local, 169.254/16 FTP Passive Mode: Yes Service Order: 7 ~~~~~~~~~~~~~~~~~~~~~~~~ Type: Ethernet\\n +Hardware.+\\n +BSD.+\\n +IPv4 Addresses: 192[\\.\\d]+\$`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions