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 = /(.*(?!\s))(?:(?<!\s\s)\:\s+)((?:[\-\+])?\d+\.\d+|\w+$|[\-\+]\d+|\w+\s\d+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(.*(?!\\s))(?:(?<!\\s\\s)\\:\\s+)((?:[\\-\\+])?\\d+\\.\\d+|\\w+$|[\\-\\+]\\d+|\\w+\\s\\d+)', 'gm') const str = `Beam Number : 2 Beam Name : CCW Original MU : 1995.39040729 Logging Scale : IEC 1217 X1 (Cms): -2.50 X2 (Cms): +2.20 Y1 (Cms): -2.60 Y2 (Cms): +2.50 Gantry Rotation Angle (deg): 87.73 Energy : 6x MU1 : 1007.63 MU2 : 1009.05 Radiation Time (mins): 1.6807 DoseRate (MU/min): 598.32 PFN High Voltage Power Supply Current (A): 1.908875 PFN Actual Voltage (KV): 18.21791 RF Driver Voltage (V): 4.365 RF Forward Power (W): 1.516418 AFC Error (V): -0.000601778 Gun Current (A): 0.3430939 Gun High Voltage (V): -14965 Gun Grid Voltage (V): 97.55565 Gun Filament Step Voltage (V): 5.300003 Gun Filament Voltage (V): 5.405273 Bend Magnet Current (A): 16.18042 Bend Magnet Voltage (V): 2.283325 Accelerator Solenoid Current (A): 34.95636 Klystron Solenoid Current (A): 34.95789 Radial Symmetry (%): 0.00045321 Transverse Symmetry (%): 0.00044355 Target Current (nC): 315.4927 Buncher Radial Current (A): 0.005020142 Buncher Transverse Current (A): -0.06005859 Angle Radial Current (A): 0.005279541 Angle Transverse Current (A): 0.06143188 Position Radial Current (A): -0.8885803 Position Transverse Current (A): -0.5808258 Trim : (A) -0.06399536 Accelerator Vacion Current (uA): 0.009002686 Positive 5V dc: 4.993916 Positive 24V dc: 24.4706 Analog Negative 5V dc: 5.054981 Analog Positive 5V dc: 4.97241 Negative 12V dc: 12.24357 Positive 3V dc: 3.303525 Node Power Supply Voltage (V): 24.58121 Water Level : Normal City Water Temperature (deg C): 20.54332 Internal Water Supply Temperature (deg C): 40.51909 Gas Pressure (PSI): 32.3421`; // 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