Get started

Free Excel add-in for curve fitting

Excel add-in for curve fitting Assayfit Pro is an Excel add-in and API service for Mac Os and Windows. Curve fitting can be performed directly from measured data in Excel or from virtually any other application. Download Add-in

Libreoffice and Openoffice templates

Assayfit pro also supports curve fitting from Libreoffice and openoffice.
Templates are available in the example section
View examples

Curve fitting in a web browser

Assayfit pro can be used directly from a web page.
Try our latest online template here by clicking on this button
fit online

Cross platform

Windows

Add-in for Microsoft Excel
Excel templates
Openoffice
Web browser
Much more

Mac

Add-in for Microsoft Excel
Excel templates
Openoffice
Web browser
Much more

Linux

Web browser
Openoffice
Python
R

Advanced reporting

The AssayFit pro add-in now generates advanced reports.
Fit graph, fit parameters and goodness of fit are shown.
The software determines the average and CV of replicates sharing
the same sample ID.

Customizeable layout

As the  report is in Excel, it  can be entirely customized.
Graph settings and rounding of the results can be changed.

Plans

Free no registration

Daily

 0€

15 curve fits per day
20 calibrators
100 unknowns
No registration required
Free templates and add-in

Get started

Free API key

2 weeks

 0€

50 curve fits
500 calibrators
500 unknowns
Registration required
Free templates and add-in

Register

Individual plan

1 Month

 9.99€

unlimited curve fits
500 calibrators
500 unknowns
individual license
Free templates and add-in

buy now

Group plan

1 month

 39.99€

unlimited curve fits
500 calibrators
500 unknowns
group license
Free templates and add-in

buy now

Features

Fit Functions

  • Linear curve fitting
  • Linear Passing-Bablok regression
  • Linear Deming regression
  • 4PL Four parameter logistic
  • 5PL Five parameter logistic
  • second order polynomial
  • third order polynomial
  • Point to point (cubic spline)
  • Univariate spline
  • your own fit function (inquire)

Fit Input parameters

  • x and y data
  • Weights
  • Custom start values
  • Apply fit limits
  • fit function
  • Extrapolate
  • Calculate unknown y value from
  • calibration curve
  • Calculate unknown x value from
  • calibration curve
  • 96 well input
  • Plate layout
  • Sample ID

Output parameters

  • xdata (your standard x values)
  • ydata (your standard y values)
  • residuals
  • weights
  • parameter start values
  • parameters after optimisation
  • SD or upper an lower limit of the
  • parameters (for some functions)
  • weighted sum of squares
  • correlation coefficient (for linear fits)
  • Calibration curve limits
  • yknown values (values of which you known the y value and want to calculate the fitted x value)
  • x values calculated from y values
  • xknown values (values of which you know the x value and want to calculate the fitted y value
  • y calculated from xknown values
  • x coordinates of the fit curve (100)
  • y coordinates of the fit curve (100)

Programming

  • Javascript curve fitting
  • Standard curve Excel
  • Dose response curve excel
  • Polynomial regression Excel
  • Excel automation example
  • Nonlinear regression in r
  • Curve fit python
  • C# curve fitting
  • VB.net template
  • (linear) regression java
  • Any other sofware which can send http get and post commands

Cross platform use

  • Excel Add-in for Mac OS and Windows
  • Libreoffice – Openoffice templates from Mac Os, Windows and Linux.
  • Software API to create your own software
  • Online curve fitting tool

Support

  • Support over email and phone (only if required)
  • Help with creating templates or software (inquire)
  • Company branding
  • Free trial of full service