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

$re = '/^\s*(\d{1,3})\s+([a-zA-z0-9-_]+\s?[a-zA-z0-9-_]+)\s+(0x[a-zA-Z0-9]{4})\s+(\d{3})\s+(\d{3})\s+(\d+)\s+([a-zA-z0-9-_]+\s?\w+)\s+(\w+)\s+-\s+(\d+)/m'; $str = 'ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 5 Reallocated_Sector_Ct 0x0033 100 100 010 Pre-fail Always - 0 9 Power_On_Hours 0x0032 096 096 000 Old_age Always - 19033 12 Power_Cycle_Count 0x0032 099 099 000 Old_age Always - 54 170 Unused_Rsvd_Blk_Ct_Chip 0x0032 100 100 010 Old_age Always - 0 171 Program_Fail_Count_Chip 0x0032 100 100 010 Old_age Always - 0 172 Erase_Fail_Count_Chip 0x0032 100 100 010 Old_age Always - 0 173 Wear_Leveling_Count 0x0033 090 090 005 Pre-fail Always - 121 174 Unexpect_Power_Loss_Ct 0x0032 099 099 000 Old_age Always - 12 178 Used_Rsvd_Blk_Cnt_Chip 0x0013 100 100 010 Pre-fail Always - 0 180 Unused_Rsvd_Blk_Cnt_Tot 0x0013 100 100 010 Pre-fail Always - 1618 184 End-to-End_Error 0x0033 100 100 097 Pre-fail Always - 0 187 Uncorrectable_Error_Cnt 0x0032 100 100 000 Old_age Always - 0 194 Temperature_Celsius 0x0032 059 055 000 Old_age Always - 41 199 CRC_Error_Count 0x003e 099 099 000 Old_age Always - 21 233 Media_Wearout_Indicator 0x0013 090 090 000 Pre-fail Always - 15085512 241 Total_LBAs_Written 0x0032 099 099 000 Old_age Always - 19103 242 Total_LBAs_Read 0x0032 099 099 000 Old_age Always - 23403 249 NAND_Writes_1GiB 0x0032 099 099 000 Old_age Always - 61952'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php