3v4l.org

run code in 300+ PHP versions simultaneously
<?php $derp = 0.29; function derp_round($derp, $len) { $mul = pow(10, $len); return floor($derp * $mul)/$mul; } var_dump( $derp, number_format($derp, 2), sprintf("%.2f", $derp), sprintf("%.2f", round($derp, 2, PHP_ROUND_HALF_DOWN)), sprintf("%.2f", derp_round($derp, 2)) );

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35.93 ms | 409 KiB | 5 Q