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+([\w-]+)\s+(0x[\da-fA-F]{4})\s+(\d{3})\s+(\d{3})\s+(\d+)\s+([\w-]+)\s+(\w+)\s+-\s+(\d+)/m'; $str = 'ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x002f 100 100 050 Pre-fail Always - 0 5 Reallocated_Sector_Ct 0x0032 100 100 001 Old_age Always - 0 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 18322 12 Power_Cycle_Count 0x0032 100 100 001 Old_age Always - 608 170 Reserved_Block_Pct 0x0033 100 100 010 Pre-fail Always - 0 171 Program_Fail_Count 0x0032 100 100 000 Old_age Always - 0 172 Erase_Fail_Count 0x0032 100 100 001 Old_age Always - 0 173 Avg_Block-Erase_Count 0x0032 100 100 000 Old_age Always - 1 174 Unexpect_Power_Loss_Ct 0x0032 100 100 000 Old_age Always - 131 183 SATA_Int_Downshift_Ct 0x0032 100 100 000 Old_age Always - 0 184 End-to-End_Error 0x0032 100 100 000 Old_age Always - 0 187 Reported_Uncorrect 0x0032 100 100 000 Old_age Always - 0 188 Command_Timeout 0x0032 100 100 000 Old_age Always - 597 194 Temperature_Celsius 0x0022 064 056 000 Old_age Always - 36 (Min/Max 16/44) 195 Hardware_ECC_Recovered 0x0032 100 100 000 Old_age Always - 0 196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0 197 Current_Pending_Sector 0x0032 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0030 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x0032 100 100 000 Old_age Always - 0 202 Percent_Lifetime_Remain 0x0030 100 100 001 Old_age Offline - 0 206 Write_Error_Rate 0x000e 100 100 000 Old_age Always - 0 246 Total_LBAs_Written 0x0032 100 100 000 Old_age Always - 582369015 247 Host_Program_Page_Count 0x0032 100 100 000 Old_age Always - 18199054 248 Bckgnd_Program_Page_Cnt 0x0032 100 100 000 Old_age Always - 22876012 180 Unused_Rsvd_Blk_Cnt_Tot 0x0033 000 000 000 Pre-fail Always - 18839 210 RAIN_Success_Recovered 0x0032 100 100 000 Old_age Always - 0 211 Integ_Scan_Complete_Cnt 0x0032 100 100 000 Old_age Always - 738 212 Integ_Scan_Folding_Cnt 0x0032 100 100 000 Old_age Always - 0'; preg_match_all($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