Time Value of Money Calculator for Mortgage Note Investors

The time value of money (TVM) is the principle that a dollar today is worth more than a dollar tomorrow because today's dollar can be invested and earn interest. Note investors use TVM math to compare a lump-sum purchase price against a future stream of monthly payments and determine the yield (IRR) on the investment.

Note investors use TVM solvers to answer questions like: "If I pay $X today for a $Y/month payment stream lasting N months, what is my annualized yield?" or "What price should I pay to hit a 12% yield on a 60-month payment stream of $400/month?" The math is the same regardless of which variable you're solving for.

PV (Present Value) is a one-time amount today — typically the purchase price or current loan balance. PMT (Payment) is a recurring amount paid at regular intervals — typically monthly. TVM math relates the two through interest and time.

The servicing fee comes out of every payment before it reaches the investor. If the gross payment is $400/mo and the servicing fee is $20/mo, the investor actually receives $380/mo. Calculating yield on $380 instead of $400 produces a lower (and accurate) annualized return. The difference between using gross vs net payment is the most common error in third-party partial-sale calculators.

End mode is the default and applies to virtually all amortizing mortgage loans — payments are due at the end of each period. Begin mode applies to lease payments and some annuity-due contracts where the payment is due at the start of the period. If you're analyzing a note, use End mode.

This calculator solves the same equations as a 10bii or HP-12C and produces the same numbers. Two differences: (1) input labels are plain English instead of cryptic abbreviations like I/YR; (2) the amortization schedule renders automatically alongside the solved variable so you can verify the math row-by-row. For most note-investor workflows, this is faster than using a separate calculator app.