Biology
DNA Copy Number Calculator
Convert a DNA sample's mass concentration into template copies per microlitre from fragment length.
Your inputs
Change any value to update the result instantly.
Template copies
15,20,74,26,162 copies/µL
Copies (scientific notation)
15.2074 ×10⁹ per µL
Mass per copy
0 pg
DNA length
3,000 bp
Uses 660 g/mol per base pair (double-stranded DNA average) and Avogadro's number. Essential for building qPCR standard curves.
What this calculator does
Converts DNA mass concentration into template copy number per microlitre for standards and quantification.
What your result means
Copies per µL of the entered sample, derived from molecular weight and Avogadro's number.
Formula and working
copies/µL = (concentration in ng/µL × 10⁻⁹ g × 6.022 × 10²³) ÷ (length bp × 660 g/mol)
- 1
Collect the inputs
DNA length = 3,000 bp; DNA concentration = 50 ng/µL
- 2
Apply the formula
copies/µL = (concentration in ng/µL × 10⁻⁹ g × 6.022 × 10²³) ÷ (length bp × 660 g/mol)
- 3
Result
Template copies = 15,207,426,162 copies/µL
Frequently asked questions
Symbols and assumptions
- L
- Template length in base pairs
- c
- Concentration in ng/µL
- Nₐ
- Avogadro's number, 6.022 × 10²³
- • Double-stranded DNA at an average 660 g/mol per base pair.
- • The concentration entered is accurate (ideally fluorometric).
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • Absorbance-based concentrations can overestimate; single-stranded templates use ~330 g/mol per base.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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