$objPHPExcel = PHPExcel_IOFactory::load('simple.xlsx');
$a = $objPHPExcel->getActiveSheet();
$highestRow = $a->getHighestRow();
$b = $a->getCell("A".$highestRow)->getValue();
int(1048576)
хотя заполнено всего 114 строк $objPHPExcel = PHPExcel_IOFactory::load("simple.xlsx");
$maxCell = $objPHPExcel->getActiveSheet()->getHighestRowAndColumn();
$data = $objPHPExcel->getActiveSheet()->rangeToArray('A1:' . $maxCell['column'] . $maxCell['row']);
$data = array_map('array_filter', $data);
$data = array_filter($data);