Before building HELOC Calculator, we checked calculator.net's HELOC calculator directly — it correctly separates the draw period (interest-only payments) from the repayment period (full principal + interest), with a clear amortization schedule showing the transition.
Heloc calculator variable rate, acknowledged but not modeled
The page's own text warns that HELOC rates "often vary over time" and flags "financial uncertainty" as a real risk. Then the calculator itself uses one fixed rate for both the draw period and the repayment period — the exact scenario it just warned you about isn't something you can actually model.
Heloc rate increase calculator, built to stress-test that risk
This tool takes two separate rates: one for the draw period, one for repayment. Set the repayment rate higher than the draw rate to see what a realistic rate increase would actually do to your payment — the risk the competitor mentions but doesn't let you calculate.
Heloc draw period interest only calculator, then the switch to real payments
Both phases are shown side by side: interest-only payment and total interest during the draw period, then the full amortizing payment and interest during repayment — plus the combined total interest across the whole loan.
