Arsal Riaz

What I actually do here

I write the amortization code, the recast logic and the explanations on this site. I want to be exact about what that is and is not: I am a developer who specialises in loan math, not a licensed mortgage broker, loan officer or financial adviser. Nothing here is a recommendation about your specific mortgage.

What I can show you is the math. The methodology page sets out the amortization formula and every assumption the recast model makes, and the update history logs changes with dates.

How the engine is checked

The amortization schedule is the foundation of every number on this site, so it is tested against fixture cases with known correct outputs rather than eyeballed. A recast is modeled the way servicers actually perform one: the lump sum is applied to principal, the remaining balance is reamortized over the remaining term, and the interest rate and maturity date stay put. That last part is what separates a recast from a refinance, and it is where most online explanations get sloppy.

Last full review: August 6, 2026.

The limits of this tool

Two honest limits. First, recast eligibility is set by your servicer, not by math. Minimum lump sums, seasoning requirements, fees and which loan types qualify all vary, and government-backed loans generally cannot be recast at all. This calculator can tell you what a recast would do; only your servicer can tell you whether you may have one.

Second, the model assumes a fixed rate and a payment that stays on schedule. It does not model escrow changes, adjustable rates, or the tax treatment of mortgage interest.

Tell me when a number is wrong

If a schedule here disagrees with your servicer's, I want the details. Send the loan terms and the figure you expected through the contact page. Confirmed corrections are fixed and logged publicly in the update history rather than quietly edited.

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