# PHP Random Number

## How to generate random number or id

Rand () function is used to generate a random number it takes two integer optional parameters. You can use mt_rand () function that generates a random number faster than and rand function function.

### Simple method to generate unique number within specific range

```<?php

\$r=rand(200,500);

printf("Unique number =%d",\$r);

?>
```

### Explanation

rand() function is a PHP built-in function that generates a unique number. If you want to generate a unique number within a range, then define the start and end point of random number. If you define the start and end point, then the unique number will be in between.
Start point = 10
End point = 100
Number can =11
Number can =99
Number cannot =101
Number cannot =09

If you have not decide the start and end point, then rand function automatically create a unique number without any range, it’s totally depend on function.

## Generate random number without specific range

```<?php

\$r=rand();

printf(" Number =%d",\$r);

?>
```

### Explanation

In this example, a random number is created without any range. It can be any number like 20, 5289, 120 etc.

## Generate random numbers using loop

```<?php

\$min=10;

\$max="100";

echo "Number between 10 to 100";

for(\$i=0;\$i<=10;\$i++)
{
\$r=rand(\$min,\$max);

printf("Nnumber =%d",\$r);
}

?>
```

### Explanation

In this example, the start point is 10 and the end point is 100 and in seventh the line there is a simple echo statement that display the statement. According to the line number 11 to 14 is a for loop that’s run 10 times, a variable \$r store the random number and printf function print 10 number.

## Generate random number using date

```<?php

\$currentdate=date('Ymd');

\$date_range=20120314;

\$number=rand(\$date_range  , \$currentdate);

echo \$number;

?>
```

### Explanation

In the above example, start point is the current date and the end point is specified in this program, so the number could be 20120312 etc.

## Complex random number

```<?php

\$time1=time();
\$t=\$time1;
\$random= rand(0,999999999);
\$a= \$t+\$random;
printf(" Random number =%d",\$a);
echo "";
\$un=  uniqid();
\$conct = \$a.\$un;
//its also refer a unique  id
printf("Random number =%d",\$conct);
\$ud = md5(\$conct.\$un);
echo "But its more accurate=";
echo \$ud;

?>
```

### Explanation

In this example first store the current date in \$time1 variable, then create a unique number from zero to 99999999 and then add unique number and time, it’s also a good random number. After that call uniqid (its create a unique id) function to a variable \$un and concatenate \$un and \$a, call md5 (calculates the MD5 hash of a string). it’s very secure.

.

Random id refer as product id in many websites.

QUOTES OF THE DAY

Saying is one thing, and doing is another.