Projects / Unofficial HAMP Loan Modification Calculator

Unofficial HAMP Loan Modification Calculator

The Unofficial HAMP Loan Modification Calculator estimates loan modification calculations using JavaScript. The code is part of an independent effort to analyze the HAMP program created by the US government to find a way to make home loans more affordable. This calculator uses the loan modification procedures disclosed in public documents such as Treasury Supplemental Directive 09-01 and the MHA Servicers Handbook v4. It includes the calculations for HAMP Tier 1 and 2, with or without principal reduction. The user can easily run one calculation, watching each step in the process in detail, or quickly obtain graphs of multiple scenarios.

Operating Systems

Recent releases

  •  16 Oct 2012 11:30

    Release Notes: Calculates both HAMP Tier 1 and Tier 2 loan modifications. Adds "schedule of payments" and "sensitivity graph" functionality. The sensitivity graph shows how Total Loan Payments, Interest Rate, or other attributes of the modified loan vary as an input such as income or home value is varied. Provides a multicolored graph for effect of rule variations (e.g. Tier 1 vs Tier 2, principal reduction vs no principal reduction). The software now uses JQuery/underscore.js/jqPlot, not prototype.js. The License is changed to "GNU GPL v2.0 or any later version" for compatibility.

    •  23 May 2012 04:06

      Release Notes: This release adds principal reduction and lender's variation calculations. The principal reduction calculation estimates the amount forgiven from the loan. The lender's variation calculation is important when more than 5% of the unpaid balance is forgiven under principal reduction, because in those cases the lender is allowed to reverse two important subsequent steps in the calculation: rate reduction and lengthening the time to pay. This release includes many minor corrections and a refactoring of the JavaScript code.

      Recent comments

      17 Jul 2010 05:02 drpaulbrewer

      Just released a new version of the calculator that "animates" the process of calculating the loan modifications instead of jumping straight to the answer. Click "Demo Site" under Links in the upper right to try it. Under the rules specified in Treasury directive 09-01, the target payment is calculated as 31% of income. First, the rate is reduced. Then, the loan is extended (up to 40 years). Then, a non-interest bearing balloon is added. (This set of rules always finds away to modify the loan, but that does not mean that the modification will be approved). Enjoy!

      15 Jul 2010 15:04 drpaulbrewer

      Click "Demo Site" under Links to use the calculator in your browser.


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