Independent loan reference, reviewed by a working broker.

Why this site exists

A standard mortgage calculator returns one number: the monthly payment. That number is the least useful piece of information the underlying math can produce. The period-by-period split between interest and principal, the effect of one extra payment per month, the difference between bi-weekly and accelerated bi-weekly — these are the figures that change financial outcomes by tens of thousands of dollars over a 25-year term, and they are exactly the figures that consumer-facing tools omit.

lefinance.xyz publishes all of them. The amortisation engine is a single readable JavaScript file. The reference content explains the underlying math in plain English. The reviewer is named, regulated, and reachable.

Editorial principles

• Three-method verification. Closed-form payment formula, period-by-period simulation, and Excel PMT()/IPMT()/PPMT() cross-check.
• Named accountability. David O'Sullivan, AMP, is the responsible reviewer. His FSRA broker licence is verifiable through the public Ontario register.
• No commission relationships. The site does not earn referral fees from any lender, broker network, or comparison site.
• No upselling. The calculator is free and contains no link to a paid version.
• Privacy by architecture. Loan amounts, rates, and any extra-payment figures stay in your browser.

The team

lefinance.xyz is operated as a small editorial project alongside David's brokerage practice. David reviews every release of the calculator and every page of reference content before publication. He holds final editorial authority and is the named accountable person for every figure on the site.

A part-time engineer in Vancouver maintains the simulator's edge-case test suite (zero-rate loans, loans with n > 480 periods, accelerated-bi-weekly rounding edge cases). The engineer is named in the public changelog only when their input has produced a substantive change.

Verification methodology

1. Reference cases. 28 input/output pairs covering zero-rate loans, single-period payoff, the boundary between “extra payment clears the balance” and “balance carries one more period,” and the accelerated-bi-weekly identity. Every release runs against the list.
2. Closed-form vs. simulation. The amortisation formula and the period-by-period loop must agree at every period boundary.
3. Excel cross-check. Inputs passed to PMT(), IPMT(), PPMT(), NPER(). All four functions must reconcile.
4. Locale rendering. Five supported currencies render via Intl.NumberFormat('en-CA') with thousand separators and zero-decimal display.

What this site is not

• It is not regulated mortgage advice. For a specific recommendation on a Canadian mortgage product, consult an FSRA-licensed broker (David's firm if you are in Ontario, or the FSRA register for any other province).
• It is not a lead-capture form. We do not pass your details to lenders or comparison sites.
• It is not a stress-test simulator. Canadian B-20 stress testing (greater of contracted rate + 2% or 5.25%) is not duplicated here.
• It is not a prepayment-penalty calculator. The Interest Rate Differential (IRD) penalty calculation depends on lender-specific posted-rate methodology, which is not modelled here.

Get in touch

Calculation queries, content corrections, accessibility issues, and partnership enquiries are all handled through the contact page. We commit to acknowledging every well-formed message within 24 business hours.