function calculatePPM() {
var soluteVal = parseFloat(document.getElementById('soluteAmount').value);
var soluteUnit = document.getElementById('soluteUnit').value;
var solutionVal = parseFloat(document.getElementById('solutionAmount').value);
var solutionUnit = document.getElementById('solutionUnit').value;
var resultBox = document.getElementById('ppm-result-box');
if (isNaN(soluteVal) || isNaN(solutionVal) || solutionVal <= 0) {
alert("Please enter valid positive numbers for both fields.");
return;
}
// Standardize solute to grams
var soluteInGrams = 0;
if (soluteUnit === 'mg') {
soluteInGrams = soluteVal / 1000;
} else if (soluteUnit === 'g') {
soluteInGrams = soluteVal;
} else if (soluteUnit === 'kg') {
soluteInGrams = soluteVal * 1000;
}
// Standardize solution to grams (Assuming density of water ~1g/ml or 1kg/L for simplicity in aqueous solutions)
var solutionInGrams = 0;
if (solutionUnit === 'L') {
solutionInGrams = solutionVal * 1000;
} else if (solutionUnit === 'ml') {
solutionInGrams = solutionVal;
} else if (solutionUnit === 'kg') {
solutionInGrams = solutionVal * 1000;
} else if (solutionUnit === 'g') {
solutionInGrams = solutionVal;
}
// PPM Calculation: (Solute mass / Solution mass) * 1,000,000
var ppm = (soluteInGrams / solutionInGrams) * 1000000;
var ppb = ppm * 1000;
var percentage = (soluteInGrams / solutionInGrams) * 100;
document.getElementById('ppm-output').innerHTML = ppm.toLocaleString(undefined, {maximumFractionDigits: 4}) + " ppm";
document.getElementById('ppb-output').innerHTML = "Equivalent to " + ppb.toLocaleString(undefined, {maximumFractionDigits: 2}) + " ppb (Parts Per Billion)";
document.getElementById('percent-output').innerHTML = "Equivalent to " + percentage.toLocaleString(undefined, {maximumFractionDigits: 6}) + "% concentration";
resultBox.style.display = 'block';
}
What is Parts Per Million (PPM)?
Parts Per Million (PPM) is a unit of measurement used to express very dilute concentrations of substances. In technical terms, 1 PPM is equivalent to one part of a substance mixed into one million parts of another. It is commonly used in water quality analysis, chemistry, and environmental science to measure contaminants, minerals, or gas levels.
The PPM Formula
PPM = (Mass of Solute / Total Mass of Solution) × 1,000,000
Common Practical Examples
Pool Chemistry: A recommended chlorine level for a swimming pool is usually between 1.0 and 3.0 ppm.
Water Purity: Lead levels in drinking water are strictly regulated; for example, the EPA action level is 0.015 ppm (or 15 ppb).
Gardening: Hydroponic nutrient solutions are often measured in PPM to ensure plants receive the correct balance of minerals.
Example Calculation
If you dissolve 50 milligrams (mg) of salt in 1 liter (1,000,000 mg) of water: