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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

Generated Code

const regex = /(?<=Street Improvements\s+).+(?=\sProject)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<=Street Improvements\\s+).+(?=\\sProject)', 'gm') const str = `Return to Contents Street Improvements Ocotillo Road – Greenfield to Higley Project #: ST0540 Project Description: Design and construction of Ocotillo Road from approximately ¼ mile east of Greenfield Road to Higley Road to minor arterial standards. The project includes crossings over the Queen Creek Wash, East Maricopa Floodway, Roosevelt Water Conservation District Canal and Chandler Heights Basin. The project includes the relocation of 69kV power lines and access into the proposed Gilbert Regional Park. Project Information: • Costs shown in prior years are for completion of an alignment study in FY 2009 to coordinate the alignment with Flood Control District projects • Maintenance costs will be determined once final design is completed. Ongoing maintenance costs will be a consideration in selection of the project design • Project is necessary for growth/development and therefore is eligible for System Development Fee funding Financial Information: Expenses: (1,000s) Total Prior FY 2021 FY 2022 FY 2023 FY 2024 FY 2025 Years 6- Beyond Years 10 10 Yrs Professional Services \$ 6,104 299 5,805 - - - - - - Construction Mgmt \$ 4,316 33 4,283 - - - - - - Land/ROW \$ 2,325 - 2,325 - - - - - - Construction \$ 53,774 - - 53,774 - - - - - Equipment & Furniture \$ - - - - - - - - - Total Expenses \$ 66,519 \$ 332 \$ 12,413 \$ 53,774 \$ - \$ - \$ - \$ - \$ - Sources: (1,000s) 2007 GO Bonds 08 \$ 246 246 - - - - - - - 2022 Potential Street Bond \$ 50,701 - - 50,701 - - - - - CIP O/S Revolving Fund \$ 375 86 289 - - - - - - Roads SDF \$ 15,197 - 12,124 3,073 - - - - - Total Sources \$ 66,519 \$ 332 \$ 12,413 \$ 53,774 \$ - \$ - \$ - \$ - \$ - Operation and Maintenance Impact: (1,000s) Personnel - - - - - Contractual Services - - - - - Supplies - - - - - Utilities - - - - - Insurance - - - - - Total O&M Impact \$ - \$ - \$ - \$ - \$ - Total Revenue \$ - \$ - \$ - \$ - \$ - 49`; 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