#dna-concentration-calculator {
max-width: 500px;
margin: 20px auto;
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#dna-concentration-calculator {
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DNA Concentration Calculator
A260 is the absorbance of the DNA solution at 260 nm wavelength. Typically, 1 A260 unit corresponds to 50 ng/μL for double-stranded DNA.
Double-stranded DNA
Single-stranded DNA
RNA
Enter A260 value and select nucleic acid type, then click “Calculate”.
Note: This calculator assumes a path length of 1 cm and uses standard conversion factors for DNA and RNA.
JavaScript is disabled. Please enable it to use the calculator. (function() { if (!document.getElementById(‘dna-concentration-calculator’)) return; const form = document.getElementById(‘calc-form’); const nucleicAcidSelect = document.getElementById(‘nucleic-acid’); const a260Input = document.getElementById(‘a260’); const resultDiv = document.getElementById(‘result’); function calculate() { resultDiv.className = ”; resultDiv.innerHTML = ”; try { const nucleicAcid = nucleicAcidSelect.value; const a260 = parseFloat(a260Input.value); let factor; if (nucleicAcid === ‘dsDNA’) { factor = 50; } else if (nucleicAcid === ‘ssDNA’) { factor = 37; } else if (nucleicAcid === ‘RNA’) { factor = 40; } if (isNaN(a260) || a260 < 0) throw new Error('Please enter a valid A260 value (non-negative number).'); const concentration = a260 * factor; resultDiv.innerHTML = ` Concentration: ${concentration.toFixed(2)} ng/μL `; resultDiv.className = ‘success’; } catch (error) { resultDiv.innerHTML = `Error: ${error.message}`; resultDiv.className = ‘error’; } } function reset() { form.reset(); resultDiv.className = ”; resultDiv.innerHTML = ‘Enter A260 value and select nucleic acid type, then click “Calculate”.’; nucleicAcidSelect.focus(); } document.getElementById(‘calculate-btn’).addEventListener(‘click’, calculate); document.getElementById(‘reset-btn’).addEventListener(‘click’, reset); form.addEventListener(‘keypress’, function(e) { if (e.key === ‘Enter’ && e.target.tagName !== ‘BUTTON’) { e.preventDefault(); calculate(); } }); })();