Protein Assay Standard Curve Calculator
Fit BCA or Bradford standards with a linear or quadratic model, inspect residuals, and interpolate dilution-corrected concentrations without uploading sample data.
Replicates are comma-separated. Prefix a replicate with ! to exclude it explicitly; no point is removed automatically.
| Use | Label | Concentration (µg/mL) | Absorbance replicates | |
|---|---|---|---|---|
Paste standards from a spreadsheet
Columns: label, concentration, replicate 1, replicate 2…
The reported original concentration equals the in-well result × dilution factor. Values outside the fitted response range are never extrapolated silently.
| Use | Sample | Absorbance replicates | Dilution factor | |
|---|---|---|---|---|
Paste unknowns from a spreadsheet
Columns: sample label, dilution factor, replicate 1, replicate 2…
How to analyze a protein assay standard curve
1. Enter measured standards
Use the concentrations and absorbance replicates from the same BCA, Bradford, or compatible colorimetric run.
2. Inspect fit quality
Review the equation, R², replicate variation, residuals, and whether the chosen model matches your kit’s validated range.
3. Interpolate unknowns
Only in-range solutions are reported. The original-sample value applies the dilution factor after interpolation.
Scientific boundaries
This tool analyzes entered assay data; it does not validate reagent preparation, incubation, plate-reader settings, protocol suitability, or diagnostic meaning. Follow the assay manufacturer’s guidance for model and working range. Quadratic fits can yield two valid concentrations for one absorbance; that ambiguity is reported instead of guessed.