Guides

These guides support the calculators and topic workflows. If you are starting from scratch, use the strongest pages first, then go deeper into the library only when you need a narrower edge case or checklist.

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Reviewed By

Written by: Practical Finance Tools Site Owner (Site owner and product editor).

Reviewed by: Practical Finance Tools Editorial Review (Editorial standards review) on 2026-04-05.

Secondary review: Practical Finance Tools Methodology Review (Formula and assumptions review).

Review scope: Guide-library curation, strongest-path surfacing, and supporting-page maintenance across the educational catalog.

See our editorial policy and methodology.

Report corrections: admin@practicalfinancetools.com

Start with the strongest guide paths

Credit card payoff strategy

Best starting page for fixed payment, minimum payment, and snowball vs avalanche decisions.

APR vs interest rate

Best starting page for understanding how fees change borrowing comparisons.

Extra mortgage payments

Best starting page for monthly extra, lump-sum, and principal-only payoff questions.

Refinance break-even

Best starting page for refinance cost, timing, and horizon decisions.

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Searches titles in the lists below.

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How to use these guides

Start with a topic hub if your question spans multiple related decisions.
Use the strongest guide first, then move into narrower pages only if you need a specific edge case.
Run the related calculator with a baseline scenario before changing inputs.
Use the checklist and FAQ sections to catch statement, fee, and timing pitfalls.

How this library is curated

The strongest workflow pages and decision-support guides are surfaced first on this index. Narrower edge-case pages remain available, but they are supporting assets rather than the best starting point for most users. Start with the clearest guide path, then move into narrower pages only when the main workflow exposes a specific question.

Credit cards

Start with the credit card payoff calculator.

APR & borrowing costs

Compare offers with the APR calculator.

FAQ

Are the guides personalized advice?

No. They explain how calculators work and how to compare scenarios using your own inputs.

Why are there multiple guides on similar topics?

Some guides are primary workflow pages, while others cover narrower edge cases. Start with the strongest pages above, then go deeper only if needed.

Mortgages

Use the mortgage payoff calculator to model extra principal.

Affordability & DTI

Start with the DTI calculator.

Rent vs buy

Start with the rent vs buy calculator.

Deeper mortgage payoff guides

After you confirm that extra principal is the workflow you need, these narrower guides help with posting rules, timing choices, PMI tradeoffs, and recast decisions.

Amortization with extra payments

See how the schedule changes after extra principal and why timing can shift the payoff path.

Principal-only extra payments

Use this when you need to make sure extra dollars reduce principal instead of getting marked as paid ahead.

One extra payment per year

Compare monthly versus annual ways to model the same payoff effect.

Biweekly vs extra principal

Compare convenience, lender program rules, and the real savings difference.

PMI removal vs extra principal

Check whether removing PMI first changes the best use of your extra cash.

Recast vs extra payments

Use this when your main question is lower required payment versus faster payoff.

Pay off early or invest?

Add liquidity, return assumptions, and risk tolerance to the mortgage payoff decision.

Want a guide?

Email admin@practicalfinancetools.com with the topic you want next. Priority requests usually come from calculators or topic workflows where users still hit the same unanswered edge case.

Updates

Guides are updated as calculators change or new scenarios are added.

Last updated: 2026-04-05