CODE EXAMPLE FOR PHP

CGST/SGST calculate in laravel 8

$preTaxAmount = '1000';
$taxPerc = 3.00; // (CGST = 1.50 + SGST = 1.50)
$gstAmount = number_format($preTaxAmount * ($taxPerc) / 100, 2, '.', '');
$postTaxAmount = number_format($preTaxAmount + $gstAmount, 2, '.', '');