Fertilizer Cost Calculator
This calculator helps you estimate the cost of fertilizer needed for your lawn or garden. It takes into account the area you need to cover, the fertilizer's coverage rate, and its price. By inputting these details, you can get a good estimate of how much you'll spend on fertilizer for your next application.
How Fertilizer Costs Are Calculated
The cost of fertilizer depends on several factors. Primarily, it's driven by the size of the area you need to treat and how effectively your chosen fertilizer product covers that area. Most fertilizer bags will state their coverage rate in square feet (sq ft) per bag. This tells you how much lawn or garden space one bag can treat.
To calculate the number of bags needed, we divide the total area you need to fertilize by the coverage rate of the fertilizer. For example, if you have a 5,000 sq ft lawn and your fertilizer covers 5,000 sq ft per bag, you'll need exactly one bag.
If your lawn is 7,500 sq ft and the fertilizer covers 5,000 sq ft per bag, you'd need 7,500 / 5,000 = 1.5 bags. Since you can't buy half a bag, you'll need to round up to 2 bags to ensure complete coverage.
Once you know the number of bags required, you multiply that number by the price of each bag to get the total estimated cost. Continuing the example, if each bag costs $45.99, and you need 2 bags, your total cost would be 2 * $45.99 = $91.98.
It's important to note that this is an estimate. Factors like uneven application, overlapping, or specific application instructions on the fertilizer packaging can affect the actual amount needed.
function calculateFertilizerCost() {
var areaToFertilize = parseFloat(document.getElementById("areaToFertilize").value);
var fertilizerCoverage = parseFloat(document.getElementById("fertilizerCoverage").value);
var fertilizerPrice = parseFloat(document.getElementById("fertilizerPrice").value);
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = ""; // Clear previous results
if (isNaN(areaToFertilize) || isNaN(fertilizerCoverage) || isNaN(fertilizerPrice) || areaToFertilize <= 0 || fertilizerCoverage <= 0 || fertilizerPrice < 0) {
resultDiv.innerHTML = "Please enter valid positive numbers for all fields.";
return;
}
var numberOfBagsNeeded = areaToFertilize / fertilizerCoverage;
var totalCost = Math.ceil(numberOfBagsNeeded) * fertilizerPrice;
resultDiv.innerHTML =
"
Number of Bags Needed: " + Math.ceil(numberOfBagsNeeded).toFixed(0) + "" +
"
Estimated Total Cost: $" + totalCost.toFixed(2) + "";
}
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font-family: sans-serif;
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padding: 20px;
border-radius: 8px;
max-width: 600px;
margin: 20px auto;
background-color: #f9f9f9;
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.calculator-wrapper h2 {
text-align: center;
color: #333;
margin-bottom: 15px;
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margin-bottom: 5px;
font-weight: bold;
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padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
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}
.calculator-result p {
margin: 5px 0;
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}
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}
.calculator-explanation h3 {
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}