AHP-OS and Farsi

Thanks to the feedback of a user from Iran, I found out that AHP-OS is working with RTL fonts like Farsi. It is important to add the semicolon to the right end of a node definition, and use latin punctuation marks, for example:

کاربری: مسکونی , تجاری , اداری ;

A simple decision hierarchy example looks like here:


Unfortunately, I am not able to check for a hierarchy with more than one level. If anyone could provide a 2 level hierarchy, I would appreciate. Arabic fonts should work too; kindly contact me, if you have an example.


Group Decision Making with AHP-OS

My AHP free online software AHP-OS has a feature to involve a group of decision makers to give their inputs to a decision problem. In contrast to my AHP Excel template, in AHP-OS the number of participants is practically unlimited. As of now, I see users having up to 100 participants in one project.

Other articles:

How to use AHP-OS for Group Decision Making?

As registered user you need to start with a new project by defining your decision hierarchy. In the Project Administration Menu click on New, define your hierarchy, Submit and Save as project. You have the possibility to give a short project description, explaining the project, before it is saved.

Continue reading Group Decision Making with AHP-OS

AHP Online Software CSV Data Export

AHP-OS allows for downloading your project data as a comma separated value text file. The following menus include a csv download key:

  • Hierarchy Input Menu – download the AHP hierarchy
  • Group Result Menu – download resulting priorities and consolidated (aggregated) decision matrix
  • Project Data Menu – download decision matrices for all individual participants

Depending on your regional settings of your PC, for each download you can select the decimal point or decimal comma as decimal separator.

Text encoding of the CVS file is UTF-8. If you are using country specific characters and Windows Excel, you can convert from UTF-8 to ANSI. Open the CSV file with notepad, and save as a new file with Encoding set to ANSI.


AHP Online Software – Latest Update 2016-10-29

Based on the request from some users I have modified the result display of my AHP-OS online software. Beside the resulting priorities it is now possible to see the underlying consolidated decision matrix, which results from the aggregation of individual judgments (AIJ) using the geometric mean.

Decision Hierarchies

For decision hierarchies the result page shows the resulting local and global priorities (overall result) in hierarchical form, and the global priorities in descending order in a bar graph.

Then, in a breakdown by nodes, consolidated priorities, consolidated decision matrix and the priorities of individual participants are shown:

As in this example, the consolidated matrix for one participant is the same as the AHP decision matrix.

Alternative Evaluation

For alternative evaluation the breakdown is done by criteria. It shows the consolidated preferences for all alternatives with respect to each of the criteria:


In this example the House A from the alternative houses A, B, C has the best match with respect to the criterion “Size”.


I am now working on the extension to let you download the complete set of input values, i.e. all underlying decision matrices, to excel. In the current version only the resulting AHP priorities are available.

AHP online software – how it was implemented

When I was asked just now in an e-mail, how my AHP online software operates,   I realized that I have never published a description about it. Therefore, here a short summary:

The AHP-OS software implementation is based on my AHP excel template. I have published one paper about it in 2013. All mathematical formulas used, are shown in this conference paper or in the excel template manual on the last 2 pages. The online version is realized in PHP, using OOP (object oriented programming), running on a Linux server.

The core module is the ahp class. It contains the routines to fill the decision matrix from the pairwise comparisons, to find the dominant eigenvalue using the power method, and to calculate the consistency ratio.

A second important class is the hierarchy class. It translates the text file – defining the hierarchy – into a hierarchical data array. When I implemented the software, I wanted to get a flexible tool, which can be used for all kind of hierarchical problems. This was actually more difficult than the implementation of all mathematical calculations, especially under the aspect of safety and malicious online attacks. The feature also differentiates the online version from the excel implementation. The excel template cannot handle hierarchies at all.

The third important class implements the database and its management. I use SQL with either sqlite or mysql drivers. There are 4 tables:

  • one for user management (registration, password, etc.),
  • one for projects (hierarchy data, description, session code etc.),
  • one for pairwise comparisons (participants, judgments etc.) and
  • one for handling alternatives.

The rest of classes contain supporting functions, like html in/output, excel download and consolidation for group results. I use a basically two open source packages, phpMailer and phpGraphlib, the rest is all realized by myself from scratch.

Please consider a donation, it will help me to maintain the website and program.

Update 2017: AHP-OS software implementation (pdf)

AHP Online Calculator – Update 2013-12-20

In this latest version of the AHP online calculator I made some changes:

  • The three judgments with highest inconsistency will be highlighted with the last column showing the recommended judgment for lowest inconsistency
  • Selection of fundamental AHP or balanced Scale
  • Number of Criteria changed from 12 to 15 max.1)
  • Length of criteria names changed from 15 to max. 20 characters
  • Download of result (decision matrix, eigen vector, CR) as csv (comma separated values) instead of txt file

The .csv  file uses “,” as field separator and “.” as decimal symbol (unchanged). Depending on your operating system it will directly open in Excel.

1) Important Note: Though the maximum number of criteria is 15, you should always try to structure your decision problem in a way that the number of criteria is in the range Seven Plus or Minus Two.