Calibration Curve Calculator (Linear Regression)

Create a calibration curve, calculate the regression line (y = mx + b), examine R², and solve for unknown concentrations with your instrument responses.

Known Data Points

Add at least three pairs of concentration (X) and response (Y) readings.

How to Use This Calculator

Begin by entering known concentration-response pairs. Each row stores a verified point from the instrument, so keep the readings tidy and avoid duplicates. Click "Add Point" to include more pairs or remove the ones you no longer want.

Type the response value measured from the unknown sample, then tap Calculate to refresh the regression line, the R² quality score, and the solved concentration.

Methodology

The tool computes the least-squares regression line (y = mx + b) using all valid (X,Y) pairs. R² is derived from the coefficient of determination, and the unknown concentration is solved by rearranging the line equation once the slope (m) and intercept (b) are known.

Why Use This Calculator

  • Instantly calculate the regression equation y = mx + b.
  • Verify the quality of your data with the R² value.
  • Find unknown concentrations from your instrument readings.
  • Visualize your data points and the best-fit line on a scatter plot.
  • Mobile-first design for use in the lab or at your desk.

Full original guide (expanded)

The audit spine for this calculator originally documented the formulas, sources, and changelog that now live in the verification panel below. Everything here maintains the same references and verification metadata so you can trace the legacy guidance.

Formulas
Formula (extracted text)
$m = \frac{n(\sum xy) - (\sum x)(\sum y)}{n(\sum x^2) - (\sum x)^2}$
Formula (extracted text)
$b = \frac{(\sum y) - m(\sum x)}{n}$
Formula (extracted text)
$R^2 = \left( \frac{n(\sum xy) - (\sum x)(\sum y)}{\sqrt{[n(\sum x^2) - (\sum x)^2] [n(\sum y^2) - (\sum y)^2]}} \right)^2$
Variables and units
  • No variables provided in audit spec.
Citations

Home — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/

Science — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/science

Chemistry — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/subcategories/chemistry

Molarity Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/molarity

Solution Dilution Calculator (M1V1=M2V2) — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/dilution

Beer-Lambert Law Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/beer-lambert-law

Percent Error Calculator — calcdomain.com · Accessed 2026-01-19
https://calcdomain.com/percent-error

Changelog
  • Version 0.1.0-draft — 2026-01-19: Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19 Version 0.1.0-draft
Version 1.5.0