Free Calibration Curve Calculator
Calculate an unknown concentration from a linear calibration curve using slope, intercept, and measured signal.
Unknown Concentration
0.000500
Unknown Concentration vs Calibration Slope (m)
Linear Calibration Curve
A calibration curve relates instrument signal to analyte concentration. With a linear model y = mx + b, an unknown concentration is found by inverting this relationship.
Formula
c_unknown = (y_measured - b) / m
where y is the measured signal, m is the slope from standard curve regression, and b is the y-intercept. The calibration curve should be established from at least 5 standard concentrations spanning the expected range.
Example Calculation
A calibration with slope = 2500 (signal/M), intercept = 0.05, and measured signal = 1.3.
- 01c = (1.3 - 0.05) / 2500
- 02c = 1.25 / 2500 = 0.000500 M = 0.500 mM
Frequently Asked Questions
Learn More
Understanding Molarity
Learn what molarity is, how to calculate it, and why it matters in chemistry. Covers moles, liters, dilution, and step-by-step examples for preparing solutions.