PHP floating number

float.php

<?php

$my_json2 = '{"tax":2.03}';
$decoded = json_decode($my_json2, true);
echo $decoded['tax'] . PHP_EOL;

$tax_in_cents = round($decoded['tax'] * 100);
$response = ['tax_cents' => intval($tax_in_cents)];
echo json_encode($response) . PHP_EOL; // => 203

$tax_in_cents = $decoded['tax'] * 100;
$response = ['tax_cents' => intval($tax_in_cents)];
echo json_encode($response) . PHP_EOL;  // => 202

Result

2.03
{"tax_cents":203}
{"tax_cents":202}