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

/
/
g

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 = "(.*)\\t(\\d*\\.\\d*[^[:space:]+\\t])"; final String string = "Electrical Parameters \n" + "Re 3.70 Ohm electrical voice coil resistance at DC\n" + "Le 0.069 mH frequency independent part of voice coil inductance\n" + "L2 0.086 mH para-inductance of voice coil\n" + "R2 1.07 Ohm electrical resistance due to eddy current losses\n" + "Cmes 110.16 µF electrical capacitance representing moving mass\n" + "Lces 12.83 mH electrical inductance representing driver compliance\n" + "Res 42.92 Ohm resistance due to mechanical losses\n" + "fs 133.9 Hz driver resonance frequency \n" + " \n" + "Mechanical Parameters \n" + "(using laser) \n" + "Mms 1.212 g mechanical mass of driver diaphragm assembly including air load and voice coil\n" + "Mmd (Sd) 1.145 g mechanical mass of voice coil and diaphragm without air load \n" + "Rms 0.256 kg/s mechanical resistance of total-driver losses\n" + "Cms 1.166 mm/N mechanical compliance of driver suspension\n" + "Kms 0.86 N/mm mechanical stiffness of driver suspension\n" + "Bl 3.317 N/A force factor (Bl product)\n" + "Lambda s 0.114 suspension creep factor\n" + " \n" + "Loss factors \n" + "Qtp 0.316 total Q-factor considering all losses\n" + "Qms 3.976 mechanical Q-factor of driver in free air considering Rms only\n" + "Qes 0.343 electrical Q-factor of driver in free air considering Re only\n" + "Qts 0.315 total Q-factor considering Re and Rms only\n" + " \n" + "Other Parameters \n" + "Vas 0.3816 l equivalent air volume of suspension \n" + "n0 0.257 % reference efficiency (2 pi-radiation using Re) \n" + "Lm 86.30 dB characteristic sound pressure level (SPL at 1m for 1W @ Re)\n" + "Lnom 86.64 dB nominal sensitivity (SPL at 1m for 1W @ Zn)\n" + " \n" + "rmse Z 4.98 % root-mean-square fitting error of driver impedance Z(f)\n" + "rmse Hx 2.97 % root-mean-square fitting error of transfer function Hx (f)\n" + " \n" + "Series resistor 0.00 Ohm resistance of series resistor\n" + "Sd 15.21 cm² diaphragm area\n\n"; final Pattern pattern = Pattern.compile(regex); 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