[madam]

<div class="col-md-12">
     <div class="card" id="count_one">
          <input type="hidden" class="idspeed" value="0.0000397938144330" />
          <div class="card-body">
               <div class="media align-items-center">
                    <input type="hidden" class="idfloat" value="10.000067981099106">
                    <div class="media-body">
                         <span  data-Count>10.00009856</span>
                         <span data-Price>0.50</span>
                         <span data-Cash>5.00006288</span>
                    </div>
               </div>
               </div>
     </div>
</div>
<div class="col-md-12">
     <div class="card" id="count_two">
          <input type="hidden" class="idspeed" value="0.0000000020431799" />
          <div class="card-body">
               <div class="media align-items-center">
                    <input type="hidden" class="idfloat" value="100.00004564566">
                    <div class="media-body">
                         <span  data-Count>100.00009856</span>
                         <span data-Price>10.50</span>
                         <span data-Cash>1050.0004567456</span>
                    </div>
               </div>
               </div>
     </div>
</div>

$(document).ready(function () {
	let cards = document.querySelectorAll('.card')

		setInterval(function () {
			cards.forEach (card => {

				const renderSpeed = card.querySelector('.idspeed').value;
				const renderPrice = card.querySelector('[data-Price]');
				const renderCount = card.querySelector('[data-Count]');
				const test = card.querySelector('.idfloat');
				const RenderSum = card.querySelector('[data-Cash]');

				test.value = parseFloat(renderSpeed / 600) + parseFloat(test.value)
				renderCount.textContent = parseFloat(test.value).toFixed(8)
				RenderSum.textContent = parseFloat(parseFloat(renderCount.textContent) * parseFloat(renderPrice.textContent)).toFixed(8)
			})

        } , 100)

});

Все вроде работает правильно ,но куча ошибок

Uncaught TypeError: Cannot read property 'value' of null
at const renderSpeed = card.querySelector('.idspeed').value;

at NodeList.forEach (<anonymous>)
at cards.forEach (card => {

const renderSpeed = card.querySelector('.idspeed').value;