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

/
/
gi

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "\\<td\\>(.{2,5})\\<\\/td\\>"; final String string = "<form method='get' action='/cgi-bin/webcmd'><pre><input type='hidden' name='screen' value='Qam'>Which EdgeQam (192.168.6.1+chassis): <input type='text' name='Qam' value='192.168.6.2'>\n" + "<input type='submit'> <input type='submit' name='qamLog' value='qamLog'></pre></form>\n" + "<h2>Mega-Bits Per Second</h2>Port = QamChannel * 16 + QamSubChannel\n" + "<table border cellspacing=0 cellpadding=5> <tr><td></td><td>PortBase</td><td>Chan</td><td>-1</td><td>-2</td><td>-3</td><td>-4</td><td>total</td></tr><tr><td>Qam1</td>\n" + "<td>16</td><td>23</td><td>4.7</td><td>4.5</td><td>6.3</td><td>0.1</td><td>15.6</td></tr>\n" + "<tr><td>Qam2</td>\n" + "<td>32</td><td>24</td><td>6.3</td><td>8.0</td><td>7.3</td><td>0.2</td><td>21.8</td></tr>\n" + "<tr><td>Qam3</td>\n" + "<td>48</td><td>25</td><td>5.6</td><td>9.9</td><td>6.0</td><td>0.2</td><td>21.6</td></tr>\n" + "<tr><td>Qam4</td>\n" + "<td>64</td><td>26</td><td>5.5</td><td>7.2</td><td>6.8</td><td>0.2</td><td>19.6</td></tr>\n" + "<tr><td>Qam5</td>\n" + "<td>80</td><td>27</td><td>8.8</td><td>4.5</td><td>7.4</td><td>0.2</td><td>21.0</td></tr>\n" + "<tr><td>Qam6</td>\n" + "<td>96</td><td>28</td><td>8.4</td><td>5.1</td><td>7.5</td><td>0.2</td><td>21.3</td></tr>\n" + "<tr><td>Qam7</td>\n" + "<td>112</td><td>29</td><td>5.9</td><td>4.5</td><td>4.5</td><td>0.2</td><td>15.0</td></tr>\n" + "<tr><td>Qam8</td>\n" + "<td>128</td><td>30</td><td>4.9</td><td>1.1</td><td>4.5</td><td>0.2</td><td>10.8</td></tr>\n" + "<tr><td>Qam9</td>\n" + "<td>144</td><td>31</td><td>4.4</td><td>4.4</td><td>4.5</td><td>0.3</td><td>13.7</td></tr>\n" + "<tr><td>Qam10</td>\n" + "<td>160</td><td>32</td><td>8.4</td><td>5.0</td><td>8.8</td><td>0.2</td><td>22.3</td></tr>\n" + "<tr><td>Qam11</td>\n" + "<td>176</td><td>OFF</td><td>0.0</td><td>0.0</td><td>0.0</td><td>0.0</td><td>0.0</td></tr>\n" + "<tr><td>Qam12</td>\n" + "<td>192</td><td>OFF</td><td>0.0</td><td>0.0</td><td>0.0</td><td>0.0</td><td>0.0</td></tr>\n" + "<tr><td>Total</td><td></td><td></td><td></td><td></td><td></td><td></td><td>182.8</td></tr></table>\n" + "<h2>Control</h2>chassisId = 1, hwVersion = 0.16, swVersion = 1.11.9, tempC = 40\n" + "MAC = c4:27:95:98:ed:eb, licenseCount = 10\n" + "<form method='get' action='/cgi-bin/webcmd'><pre><input type='hidden' name='screen' value='qamControlWrite'><input type='hidden' name='qamIp' value='192.168.6.2'><input type='hidden' name='modulationMode' value='1'><input type='hidden' name='qamMode' value='4'>baseChannel: A=<input type='text' name='baseChannel0' value='23' size='3'> B=<input type='text' name='baseChannel1' value='27' size='3'> C=<input type='text' name='baseChannel2' value='31' size='3'> \n" + "<input type='hidden' name='strengthPercent0' value='95' size='3'><input type='hidden' name='strengthPercent1' value='95' size='3'><input type='hidden' name='strengthPercent2' value='95' size='3'>carrierOn: A=<input type='text' name='carrierOn0' value='1' size='1'><input type='text' name='carrierOn1' value='1' size='1'><input type='text' name='carrierOn2' value='1' size='1'><input type='text' name='carrierOn3' value='1' size='1'> B=<input type='text' name='carrierOn4' value='1' size='1'><input type='text' name='carrierOn5' value='1' size='1'><input type='text' name='carrierOn6' value='1' size='1'><input type='text' name='carrierOn7' value='1' size='1'> C=<input type='text' name='carrierOn8' value='1' size='1'><input type='text' name='carrierOn9' value='1' size='1'><input type='text' name='carrierOn10' value='0' size='1'><input type='text' name='carrierOn11' value='0' size='1'> \n" + "alternateIp: <input type='text' name='alternateIp' value='192.168.6.99'>\n" + "<input type='hidden' name='macAddress' value='c4:27:95:98:ed:eb'>tftpIp: <input type='text' name='tftpIp' value='192.168.100.3'>\n" + "tftpFilename: <input type='text' name='tftpFilename' value='' size='60'>\n" + "reset: <input type='text' name='reset' value='0'>\n" + "<input type='submit'>\n" + "</pre></form>"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html