Calculator
Result
Concentration: 1.000e-5 M
Equivalent: 10 µM
Amount: 1.000e-9 mol
Equivalent: 1 nmol
Equivalent: 1000 pmol
Use absorbance, extinction coefficient, path length, and sample volume to estimate the amount of absorbing molecule.
This is useful when the extinction coefficient is known and the absorbance reading is within a reliable measurement range.
Use this calculator as a planning aid for molecular biology, biochemistry, protein science, cloning, PCR, and routine bench preparation workflows.
Results should be interpreted alongside your protocol, instrument settings, reagent quality, and laboratory safety requirements.
How to cite this tool
If this calculator supports your research, you may cite it as a web-based tool.
Abdulfattah, M. A. Absorbance to Moles Calculator. Mustafa A Abdulfattah Academic Website. Available at: https://www.mustafaabdulfattah.com/tools/absorbance-to-moles-calculator. Accessed today.
@misc{abdulfattah_absorbance_to_moles_calculator_2026,
author = {Abdulfattah, Mustafa A.},
title = {Absorbance to Moles Calculator},
year = {2026},
url = {https://www.mustafaabdulfattah.com/tools/absorbance-to-moles-calculator},
note = {Accessed today}
}FAQ
This calculator expects a molar extinction coefficient in M-1 cm-1.
Path length is the optical distance through the sample, commonly 1 cm in standard cuvettes.
It outputs molar concentration and estimated amount in moles, nmol, and pmol.
Yes. Turbidity, contaminants, and instrument limitations can affect absorbance-based estimates.