# uimuldw > Compute the double word product of two unsigned 32-bit integers.
## Usage ```javascript var uimuldw = require( '@stdlib/math/base/special/uimuldw' ); ``` #### uimuldw( \[out,] a, b ) Multiplies two unsigned 32-bit integers and returns an `array` of two unsigned 32-bit integers (in big endian order) which represents the unsigned 64-bit integer product. ```javascript var v = uimuldw( 1, 10 ); // returns [ 0, 10 ] v = uimuldw( 0x80000000, 0x80000000 ); // 2^31 * 2^31 = 4611686018427388000 => 32-bit integer overflow // returns [ 1073741824, 0 ] ```
## Notes - When computing the product of 32-bit integer values in double-precision floating-point format (the default JavaScript numeric data type), computing the double word product is necessary in order to **avoid** exceeding the [maximum safe double-precision floating-point integer value][@stdlib/constants/float64/max-safe-integer].
## Examples ```javascript var lpad = require( '@stdlib/string/left-pad' ); var uimuldw = require( '@stdlib/math/base/special/uimuldw' ); var i; var j; var y; for ( i = 0xFFFFFFF0; i < 0xFFFFFFFF; i++ ) { for ( j = i; j < 0xFFFFFFFF; j++) { y = uimuldw( i, j ); console.log( '%d x %d = 0x%s%s', i, j, lpad( y[0].toString( 16 ), 8, '0' ), lpad( y[1].toString( 16 ), 8, '0' ) ); } } ```