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

Substitution

Processing...

Code Generator

Language

Generated Code

re = /^(\S+)\s+(\S+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\%\s+(.*)$/m str = 'udev devtmpfs 65928068 0 65928068 0% /dev tmpfs tmpfs 13190576 304608 12885968 3% /run /dev/mapper/pve-root ext4 98559220 50337808 43171864 54% / tmpfs tmpfs 65952876 46800 65906076 1% /dev/shm tmpfs tmpfs 5120 0 5120 0% /run/lock tmpfs tmpfs 65952876 0 65952876 0% /sys/fs/cgroup /dev/sda2 vfat 523248 324 522924 1% /boot/efi /dev/fuse fuse 30720 24 30696 1% /etc/pve tmpfs tmpfs 13190572 0 13190572 0% /run/user/0 /dev/sdb1 ext4 960302804 6446016 905002328 1% /mnt/pve/discousb' subst = '' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html