Fastest way to convert string to integer in PHP

Question

Using PHP  what s the fastest way to convert a string like this   123  to an integer   Why is that particular method the fastest  What happens if it gets unexpected input  such as  hello  or an array

User · Answer

I personally feel casting is the prettiest.

$iSomeVar = (int) $sSomeOtherVar;

Should a string like 'Hello' be sent, it will be cast to integer 0. For a string such as '22 years old', it will be cast to integer 22. Anything it can't parse to a number becomes 0.

If you really do NEED the speed, I guess the other suggestions here are correct in assuming that coercion is the fastest.

User · Answer

Run a test       string coerce           7 42296099663    string cast             8 05654597282    string fail coerce      7 14159703255    string fail cast        7 87444186211   This was a test that ran each scenario 10 000 000 times   -   Co-ercion is 0    123   Casting is  integer  123   I think Co-ercion is a tiny bit faster  Oh  and trying 0   array  123   is a fatal error in PHP  You might want your code to check the type of the supplied value   My test code is below     function test string coerce  s        return 0    s     function test string cast  s        return  integer  s      iter   10000000   print  -- running each text  iter times  n       string co-erce  string coerce   new Timer   string coerce- gt Start     print  String Coerce test n   for   i   0   i  lt   iter    i           test string coerce  123        string coerce- gt Stop        string cast  string cast   new Timer   string cast- gt Start     print  String Cast test n   for   i   0   i  lt   iter    i           test string cast  123        string cast- gt Stop        string co-erce fail   string coerce fail   new Timer   string coerce fail- gt Start     print  String Coerce fail test n   for   i   0   i  lt   iter    i           test string coerce  hello        string coerce fail- gt Stop        string cast fail  string cast fail   new Timer   string cast fail- gt Start     print  String Cast fail test n   for   i   0   i  lt   iter    i           test string cast  hello        string cast fail- gt Stop        ----------------- print   n   print  string coerce              string coerce- gt Elapsed     n   print  string cast                string cast- gt Elapsed     n   print  string fail coerce         string coerce fail- gt Elapsed     n   print  string fail cast           string cast fail- gt Elapsed     n     class Timer       var  ticking   null      var  started at   false      var  elapsed   0       function Timer              this- gt ticking   null             function Start              this- gt ticking   true           this- gt started at   microtime TRUE              function Stop             if   this- gt ticking                this- gt elapsed   microtime TRUE  -  this- gt started at           this- gt ticking   false             function Elapsed             switch   this- gt ticking                 case true  return  Still Running               case false  return  this- gt elapsed              case null  return  Not Started

User · Answer

Ran a benchmark  and it turns out the fastest way of getting a real integer  using all the available methods  is   foo    int   12 345     Just using    foo     12 345     returns a float

User · Answer

Run a test       string coerce           7 42296099663    string cast             8 05654597282    string fail coerce      7 14159703255    string fail cast        7 87444186211   This was a test that ran each scenario 10 000 000 times   -   Co-ercion is 0    123   Casting is  integer  123   I think Co-ercion is a tiny bit faster  Oh  and trying 0   array  123   is a fatal error in PHP  You might want your code to check the type of the supplied value   My test code is below     function test string coerce  s        return 0    s     function test string cast  s        return  integer  s      iter   10000000   print  -- running each text  iter times  n       string co-erce  string coerce   new Timer   string coerce- gt Start     print  String Coerce test n   for   i   0   i  lt   iter    i           test string coerce  123        string coerce- gt Stop        string cast  string cast   new Timer   string cast- gt Start     print  String Cast test n   for   i   0   i  lt   iter    i           test string cast  123        string cast- gt Stop        string co-erce fail   string coerce fail   new Timer   string coerce fail- gt Start     print  String Coerce fail test n   for   i   0   i  lt   iter    i           test string coerce  hello        string coerce fail- gt Stop        string cast fail  string cast fail   new Timer   string cast fail- gt Start     print  String Cast fail test n   for   i   0   i  lt   iter    i           test string cast  hello        string cast fail- gt Stop        ----------------- print   n   print  string coerce              string coerce- gt Elapsed     n   print  string cast                string cast- gt Elapsed     n   print  string fail coerce         string coerce fail- gt Elapsed     n   print  string fail cast           string cast fail- gt Elapsed     n     class Timer       var  ticking   null      var  started at   false      var  elapsed   0       function Timer              this- gt ticking   null             function Start              this- gt ticking   true           this- gt started at   microtime TRUE              function Stop             if   this- gt ticking                this- gt elapsed   microtime TRUE  -  this- gt started at           this- gt ticking   false             function Elapsed             switch   this- gt ticking                 case true  return  Still Running               case false  return  this- gt elapsed              case null  return  Not Started

User · Answer

I ve just set up a quick benchmarking exercise   Function             time to run 1 million iterations --------------------------------------------  int   123                  0 55029 intval  123                 1 0115   183     int   0                    0 42461 intval  0                   0 95683  225     int  int                   0 1502 intval int                  0 65716  438     int  array  a    b         0 91264 intval array  a    b        1 47681  162     int   hello                0 42208 intval  hello               0 93678  222     On average  calling intval   is two and a half times slower  and the difference is the greatest if your input already is an integer   I d be interested to know why though     Update  I ve run the tests again  this time with coercion  0    var     INPUT   x           int   x   intval  x     0    x      ----------------- ------------ ----------- -----------     123                0 51541     0 96924     0 33828       0                  0 42723     0 97418     0 31353      123                 0 15011     0 61690     0 15452      array  a    b       0 8893      1 45109     err           hello              0 42618     0 88803     0 1691      ----------------- ------------ ----------- -----------    Addendum  I ve just come across a slightly unexpected behaviour which you should be aware of when choosing one of these methods    x    11    int   x          int 11  intval  x         int 11   x   0            int 11    x    0x11    int   x          int 0  intval  x         int 0   x   0            int 17      x    011    int   x          int 11  intval  x         int 11   x   0            int 11   not 9    Tested using PHP 5 3 1

User · Answer

int   settype  100    integer      convert the numeric string to int

User · Answer

I personally feel casting is the prettiest.

$iSomeVar = (int) $sSomeOtherVar;

Should a string like 'Hello' be sent, it will be cast to integer 0. For a string such as '22 years old', it will be cast to integer 22. Anything it can't parse to a number becomes 0.

If you really do NEED the speed, I guess the other suggestions here are correct in assuming that coercion is the fastest.

User · Answer

You can simply convert long string into integer by using FLOAT   float    float  num    Or if you want integer not floating val then go with   float    int  num    For ex    int     1212 3      1212   float   1212 3      1212 3

User · Answer

More ad-hoc benchmark results     time php -r  for   x   0  x  lt  999999999   x     i    integer   -11           real    2m10 397s user    2m10 220s sys     0m0 025s    time php -r  for   x   0  x  lt  999999999   x     i     -11                    real    2m1 724s user    2m1 635s sys     0m0 009s    time php -r  for   x   0  x  lt  999999999   x     i      -11                   real    1m21 000s user    1m20 964s sys     0m0 007s

User · Answer

I ve just set up a quick benchmarking exercise   Function             time to run 1 million iterations --------------------------------------------  int   123                  0 55029 intval  123                 1 0115   183     int   0                    0 42461 intval  0                   0 95683  225     int  int                   0 1502 intval int                  0 65716  438     int  array  a    b         0 91264 intval array  a    b        1 47681  162     int   hello                0 42208 intval  hello               0 93678  222     On average  calling intval   is two and a half times slower  and the difference is the greatest if your input already is an integer   I d be interested to know why though     Update  I ve run the tests again  this time with coercion  0    var     INPUT   x           int   x   intval  x     0    x      ----------------- ------------ ----------- -----------     123                0 51541     0 96924     0 33828       0                  0 42723     0 97418     0 31353      123                 0 15011     0 61690     0 15452      array  a    b       0 8893      1 45109     err           hello              0 42618     0 88803     0 1691      ----------------- ------------ ----------- -----------    Addendum  I ve just come across a slightly unexpected behaviour which you should be aware of when choosing one of these methods    x    11    int   x          int 11  intval  x         int 11   x   0            int 11    x    0x11    int   x          int 0  intval  x         int 0   x   0            int 17      x    011    int   x          int 11  intval  x         int 11   x   0            int 11   not 9    Tested using PHP 5 3 1

User · Answer

I ve just set up a quick benchmarking exercise   Function             time to run 1 million iterations --------------------------------------------  int   123                  0 55029 intval  123                 1 0115   183     int   0                    0 42461 intval  0                   0 95683  225     int  int                   0 1502 intval int                  0 65716  438     int  array  a    b         0 91264 intval array  a    b        1 47681  162     int   hello                0 42208 intval  hello               0 93678  222     On average  calling intval   is two and a half times slower  and the difference is the greatest if your input already is an integer   I d be interested to know why though     Update  I ve run the tests again  this time with coercion  0    var     INPUT   x           int   x   intval  x     0    x      ----------------- ------------ ----------- -----------     123                0 51541     0 96924     0 33828       0                  0 42723     0 97418     0 31353      123                 0 15011     0 61690     0 15452      array  a    b       0 8893      1 45109     err           hello              0 42618     0 88803     0 1691      ----------------- ------------ ----------- -----------    Addendum  I ve just come across a slightly unexpected behaviour which you should be aware of when choosing one of these methods    x    11    int   x          int 11  intval  x         int 11   x   0            int 11    x    0x11    int   x          int 0  intval  x         int 0   x   0            int 17      x    011    int   x          int 11  intval  x         int 11   x   0            int 11   not 9    Tested using PHP 5 3 1

User · Answer

integer excract from any string   in    tel 123-12-33    preg match all    d      in   matches    out     int implode      matches 0         out   1231233

User · Answer

More ad-hoc benchmark results     time php -r  for   x   0  x  lt  999999999   x     i    integer   -11           real    2m10 397s user    2m10 220s sys     0m0 025s    time php -r  for   x   0  x  lt  999999999   x     i     -11                    real    2m1 724s user    2m1 635s sys     0m0 009s    time php -r  for   x   0  x  lt  999999999   x     i      -11                   real    1m21 000s user    1m20 964s sys     0m0 007s

User · Answer

int   settype  100    integer      convert the numeric string to int

User · Answer

I ve just set up a quick benchmarking exercise   Function             time to run 1 million iterations --------------------------------------------  int   123                  0 55029 intval  123                 1 0115   183     int   0                    0 42461 intval  0                   0 95683  225     int  int                   0 1502 intval int                  0 65716  438     int  array  a    b         0 91264 intval array  a    b        1 47681  162     int   hello                0 42208 intval  hello               0 93678  222     On average  calling intval   is two and a half times slower  and the difference is the greatest if your input already is an integer   I d be interested to know why though     Update  I ve run the tests again  this time with coercion  0    var     INPUT   x           int   x   intval  x     0    x      ----------------- ------------ ----------- -----------     123                0 51541     0 96924     0 33828       0                  0 42723     0 97418     0 31353      123                 0 15011     0 61690     0 15452      array  a    b       0 8893      1 45109     err           hello              0 42618     0 88803     0 1691      ----------------- ------------ ----------- -----------    Addendum  I ve just come across a slightly unexpected behaviour which you should be aware of when choosing one of these methods    x    11    int   x          int 11  intval  x         int 11   x   0            int 11    x    0x11    int   x          int 0  intval  x         int 0   x   0            int 17      x    011    int   x          int 11  intval  x         int 11   x   0            int 11   not 9    Tested using PHP 5 3 1

User · Answer

I personally feel casting is the prettiest.

$iSomeVar = (int) $sSomeOtherVar;

Should a string like 'Hello' be sent, it will be cast to integer 0. For a string such as '22 years old', it will be cast to integer 22. Anything it can't parse to a number becomes 0.

If you really do NEED the speed, I guess the other suggestions here are correct in assuming that coercion is the fastest.

User · Answer

You can simply convert long string into integer by using FLOAT   float    float  num    Or if you want integer not floating val then go with   float    int  num    For ex    int     1212 3      1212   float   1212 3      1212 3

User · Answer

Run a test       string coerce           7 42296099663    string cast             8 05654597282    string fail coerce      7 14159703255    string fail cast        7 87444186211   This was a test that ran each scenario 10 000 000 times   -   Co-ercion is 0    123   Casting is  integer  123   I think Co-ercion is a tiny bit faster  Oh  and trying 0   array  123   is a fatal error in PHP  You might want your code to check the type of the supplied value   My test code is below     function test string coerce  s        return 0    s     function test string cast  s        return  integer  s      iter   10000000   print  -- running each text  iter times  n       string co-erce  string coerce   new Timer   string coerce- gt Start     print  String Coerce test n   for   i   0   i  lt   iter    i           test string coerce  123        string coerce- gt Stop        string cast  string cast   new Timer   string cast- gt Start     print  String Cast test n   for   i   0   i  lt   iter    i           test string cast  123        string cast- gt Stop        string co-erce fail   string coerce fail   new Timer   string coerce fail- gt Start     print  String Coerce fail test n   for   i   0   i  lt   iter    i           test string coerce  hello        string coerce fail- gt Stop        string cast fail  string cast fail   new Timer   string cast fail- gt Start     print  String Cast fail test n   for   i   0   i  lt   iter    i           test string cast  hello        string cast fail- gt Stop        ----------------- print   n   print  string coerce              string coerce- gt Elapsed     n   print  string cast                string cast- gt Elapsed     n   print  string fail coerce         string coerce fail- gt Elapsed     n   print  string fail cast           string cast fail- gt Elapsed     n     class Timer       var  ticking   null      var  started at   false      var  elapsed   0       function Timer              this- gt ticking   null             function Start              this- gt ticking   true           this- gt started at   microtime TRUE              function Stop             if   this- gt ticking                this- gt elapsed   microtime TRUE  -  this- gt started at           this- gt ticking   false             function Elapsed             switch   this- gt ticking                 case true  return  Still Running               case false  return  this- gt elapsed              case null  return  Not Started

User · Answer

Ran a benchmark  and it turns out the fastest way of getting a real integer  using all the available methods  is   foo    int   12 345     Just using    foo     12 345     returns a float

User · Answer

integer excract from any string   in    tel 123-12-33    preg match all    d      in   matches    out     int implode      matches 0         out   1231233

User · Answer

I personally feel casting is the prettiest.

$iSomeVar = (int) $sSomeOtherVar;

Should a string like 'Hello' be sent, it will be cast to integer 0. For a string such as '22 years old', it will be cast to integer 22. Anything it can't parse to a number becomes 0.

If you really do NEED the speed, I guess the other suggestions here are correct in assuming that coercion is the fastest.

User · Answer

Run a test       string coerce           7 42296099663    string cast             8 05654597282    string fail coerce      7 14159703255    string fail cast        7 87444186211   This was a test that ran each scenario 10 000 000 times   -   Co-ercion is 0    123   Casting is  integer  123   I think Co-ercion is a tiny bit faster  Oh  and trying 0   array  123   is a fatal error in PHP  You might want your code to check the type of the supplied value   My test code is below     function test string coerce  s        return 0    s     function test string cast  s        return  integer  s      iter   10000000   print  -- running each text  iter times  n       string co-erce  string coerce   new Timer   string coerce- gt Start     print  String Coerce test n   for   i   0   i  lt   iter    i           test string coerce  123        string coerce- gt Stop        string cast  string cast   new Timer   string cast- gt Start     print  String Cast test n   for   i   0   i  lt   iter    i           test string cast  123        string cast- gt Stop        string co-erce fail   string coerce fail   new Timer   string coerce fail- gt Start     print  String Coerce fail test n   for   i   0   i  lt   iter    i           test string coerce  hello        string coerce fail- gt Stop        string cast fail  string cast fail   new Timer   string cast fail- gt Start     print  String Cast fail test n   for   i   0   i  lt   iter    i           test string cast  hello        string cast fail- gt Stop        ----------------- print   n   print  string coerce              string coerce- gt Elapsed     n   print  string cast                string cast- gt Elapsed     n   print  string fail coerce         string coerce fail- gt Elapsed     n   print  string fail cast           string cast fail- gt Elapsed     n     class Timer       var  ticking   null      var  started at   false      var  elapsed   0       function Timer              this- gt ticking   null             function Start              this- gt ticking   true           this- gt started at   microtime TRUE              function Stop             if   this- gt ticking                this- gt elapsed   microtime TRUE  -  this- gt started at           this- gt ticking   false             function Elapsed             switch   this- gt ticking                 case true  return  Still Running               case false  return  this- gt elapsed              case null  return  Not Started

[php] Fastest way to convert string to integer in PHP

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