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October, 2018

Colorado Child Support Version 2019, incorporating the new law, is now available.

Version 2019 is available through its own new web site, www.colochildsupport.com


Legal Math is now in use by over 4200 lawyers nationwide.


Legal Math, is Windows XP, 7 and 10 compatible.



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Specialized reliable software for lawyers since 1989  
Before purchasing this desktop program, you should know that the features of Legal Math are now available as a web service.  This new service, which is based on Legal Math, allows you to use your favorite modern browser, on PCs, Apple, and Android devices, to do the same tasks performed by the desktop version of Legal Math.  Details can be found at www.math4law.com  A generous free trial of this web based service is available.  No credit card is required for this free trial.  You are encouraged to try it.


Legal Math™ is a collection of law practice related math applications including a very specialized program to calculate interest on past due child support, child support arrearage or other situations involving irregular charges and payments.  The program has settings you can configure for calculation method differences for Colorado, California, Washington, Oregon, Illinois, Oklahoma, Indiana, Texas (and every other State, as well).  This program is extremely flexible and user friendly.*  (Windows XP, 7 and 10 compatible.)  
Click here to start the purchase process if you are are a new user or here if you are updating as a prior user..
  • In addition to being able to calculate interest on child support arrearage (interest on past due child support in a child support collection case), Legal Math can easily perform an interest calculation in a debt collection case when you need to determine interest on a judgment or other unpaid account.  This software is more than family law software, and is not just for child support lawyers.  It is also applicable to calculating interest in a wide variety of personal and business related situations involving irregular payments.
  • This program has been in use by Law Firms, Courts and Child Support Agencies throughout the United States for nearly 30 years.
  • Please examine additional features that will make you money and save you time.
  • Please examine the Data Entry Screen to see a short sample calculation of interest on past due child support.
  • Please look at the Press Release (pdf file)
  • Click here to start the purchase process if you are are a new user.
  • Click here if you are updating as a prior user.


Other programs
The following are other programs developed and sold by Custom Legal Software:
Colorado Child Support Guidelines program to calculate child support under Colorado law.  (Version 2019, incorporating the new law, is now available. 
Colorado Financial Affidavit - no longer sold by Custom Legal Software.

* Legal Math Geographical distribution:

Legal Math has a significant presence among family law lawyers and collection lawyers in the following states:  (The program is primarily used in these states to calculate interest on past due child support and to calculate interest on other types of past due accounts involving judgments, garnishments and irregular charges and payments.)

Arizona  California  Colorado  Georgia  Illinois  Indiana  Iowa  Louisiana  Maine Missouri  Nebraska  New Jersey  New Mexico  Oklahoma  Oregon  Pennsylvania Texas  Washington  Wisconsin

Legal Math also has a modest presence among family law lawyers and collection lawyers in the following states:

Alabama  Alaska  Arkansas  Connecticut  Florida  Idaho  Kansas  Kentucky Louisiana  Michigan  Minnesota  Mississippi  Nevada  New York  Ohio  Tennessee  Utah  Virginia  Wyoming.

There are Legal Math users in most of the rest of the states, as well, but not enough for us to be bragging about them  -  yet.

 Legal Math is used by Governmental Child Support Enforcement Offices in parts of California, Colorado, Nebraska, Oklahoma and Wisconsin.

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October, 2018

Custom Legal Software
760 Club Circle
Louisville, Colorado  80027

Contact: William Redak

Downloads for those who already have a license for the current version of Legal Math:

If you are a current registered user, there is no charge to download the program "setup" file. 

You do not need your Activation Code to download the "setup" file.

You do not need your Activation Code to install the "setup" file.

You will need your Activation Code before you are able to actually use the program after it has been installed.

Legal Math program: Please start at the Customer Support section of this web site.  Click on the Customer Support link in the upper left portion of this screen.

Colorado Child Support program: This program, revised because of changes in the law effective January 1, 2019, is now available through its own new web site: www.colochildsupport.com