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

$re = '/url\=(?<url>[^ ]*)/m'; $str = 'rec_type=71 tcp_flags=0 sec_intel_event=No monitor_rule_8=0 client_version="" monitor_rule_7=N/A monitor_rule_4=N/A snmp_out=0 monitor_rule_2=N/A ssl_server_name="" monitor_rule_1=N/A dest_pkts=8 sensor=ipkdol02p last_pkt_sec=1574690104 ssl_flow_error=0 ssl_url_category=0 src_ip=10.140.6.154 ssl_rule_id=0 dns_rec_id=0 src_port=59057 ssl_cert_fingerprint=0000000000000000000000000000000000000000 monitor_rule_6=N/A rec_type_simple=RNA event_desc="Flow Statistics" first_pkt_sec=1574690104 security_context=00000000000000000000000000000000 netflow_src=00000000-0000-0000-0000-000000000000 has_ipv6=1 monitor_rule_5=N/A ssl_actual_action=Unknown src_autonomous_system=0 src_bytes=863 connection_id=40461 event_usec=0 dest_autonomous_system=0 dest_mask=0 monitor_rule_3=N/A dest_ip_country="united states" iface_ingress=vrf client_app="SSL client" user_agent="" ssl_flow_status=Unknown snmp_in=0 file_count=0 dest_ip=216.58.193.142 ssl_ticket_id=0000000000000000000000000000000000000000 dest_tos=0 fw_rule_reason=N/A sinkhole_uuid=00000000-0000-0000-0000-000000000000 fw_policy=00000000-0000-0000-0000-00005dd129e8 sec_intel_ip=N/A ssl_flow_messages=0 ssl_cipher_suite=TLS_NULL_WITH_NULL_NULL http_referrer="" src_mask=0 legacy_ip_address=0.0.0.0 ssl_version=Unknown ssl_flow_flags=0 event_sec=1574693323 dns_query="" url_category="Search Engines" ip_proto=TCP dest_port=443 url=https://fcmatch.google.com ssl_server_cert_status="Not Checked" mac_address=00:00:00:00:00:00 netbios_domain="" dns_ttl=0 src_tos=0 ssl_policy_id=00000000000000000000000000000000 ssl_session_id=0000000000000000000000000000000000000000000000000000000000000000 iface_egress=outside num_ioc=0 referenced_host="" event_type=1003 dest_bytes=4538 dns_resp_id=0 user="No Authentication Required" ip_layer=0 fw_rule="Default Action" fw_rule_action=Allow rec_type_desc="Connection Statistics" ssl_expected_action=Unknown app_proto=HTTPS vlan_id=0 sec_zone_ingress=Internal-ASA sec_zone_egress=External-ASA event_subtype=1 http_response=0 web_app=Google url_reputation="Well known" src_ip_country=unknown src_pkts=8 instance_id=1 ips_count=0 rec_type=71 tcp_flags=0 sec_intel_event=No monitor_rule_8=0 client_version="" monitor_rule_7=N/A monitor_rule_4=N/A snmp_out=0 monitor_rule_2=N/A ssl_server_name="" monitor_rule_1=N/A dest_pkts=10 sensor=ipkdol02p last_pkt_sec=1574690104 ssl_flow_error=0 ssl_url_category=0 src_ip=10.140.6.154 ssl_rule_id=0 dns_rec_id=0 src_port=59066 ssl_cert_fingerprint=0000000000000000000000000000000000000000 monitor_rule_6=N/A rec_type_simple=RNA event_desc="Flow Statistics" first_pkt_sec=1574690104 security_context=00000000000000000000000000000000 netflow_src=00000000-0000-0000-0000-000000000000 has_ipv6=1 monitor_rule_5=N/A ssl_actual_action=Unknown src_autonomous_system=0 src_bytes=2750 connection_id=40463 event_usec=0 dest_autonomous_system=0 dest_mask=0 monitor_rule_3=N/A dest_ip_country="united states" iface_ingress=vrf client_app="SSL client" user_agent="" ssl_flow_status=Unknown snmp_in=0 file_count=0 dest_ip=198.8.70.129 ssl_ticket_id=0000000000000000000000000000000000000000 dest_tos=0 fw_rule_reason=N/A sinkhole_uuid=00000000-0000-0000-0000-000000000000 fw_policy=00000000-0000-0000-0000-00005dd129e8 sec_intel_ip=N/A ssl_flow_messages=0 ssl_cipher_suite=TLS_NULL_WITH_NULL_NULL http_referrer="" src_mask=0 legacy_ip_address=0.0.0.0 ssl_version=Unknown ssl_flow_flags=0 event_sec=1574693323 dns_query="" url_category="Web Advertisements" ip_proto=TCP dest_port=443 url=https://p.rfihub.com ssl_server_cert_status="Not Checked" mac_address=00:00:00:00:00:00 netbios_domain="" dns_ttl=0 src_tos=0 ssl_policy_id=00000000000000000000000000000000 ssl_session_id=0000000000000000000000000000000000000000000000000000000000000000 iface_egress=outside num_ioc=0 referenced_host="" event_type=1003 dest_bytes=4843 dns_resp_id=0 user="No Authentication Required" ip_layer=0 fw_rule="Default Action" fw_rule_action=Allow rec_type_desc="Connection Statistics" ssl_expected_action=Unknown app_proto=HTTPS vlan_id=0 sec_zone_ingress=Internal-ASA sec_zone_egress=External-ASA event_subtype=1 http_response=0 web_app="Rocket Fuel" url_reputation="Benign sites with security risks" src_ip_country=unknown src_pkts=11 instance_id=1 ips_count=0'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php