# Instead

> Amortization, refinancing, extra payments, prepay versus invest, rent versus buy. Every decision held against its alternative, computed to the cent, entirely in your browser.

Instead is a single-page application. It has one URL: https://instead.fyi/. Views are
selected with a hash fragment, which is never sent to a server, so there are no
other pages to crawl. Everything below is reachable from that one address.

- Every screen holds one decision against its alternative and stops short of naming a winner. The tradeoffs are real and they belong to whoever signs.
- Money is integer cents, never floating point. Rate arithmetic runs through decimal.js with half-up rounding, and the final payment absorbs the rounding residue, so a thirty-year monthly schedule closes on payment 360 rather than leaking into a phantom 361st.
- Nothing you type leaves your browser. There is no account, no backend and no stored data, and the Content-Security-Policy ships connect-src 'self' so the browser enforces it rather than the claim resting on trust.
- Every number printed in the application's own prose is recomputed from the engine by a test, so the words cannot drift from the math.

## Full text

- [Complete description](https://instead.fyi/llms-full.txt): every view, every question and every defined term, in one file.

## Views

- [Mortgage explorer](https://instead.fyi/#/mortgage): Amortization, extra payments, milestones and the full table.
- [What-if sliders](https://instead.fyi/#/what-if): Move sliders and watch the whole picture move.
- [Scenario comparison](https://instead.fyi/#/scenarios): Side-by-side metrics for every saved scenario.
- [Refinance](https://instead.fyi/#/refinance): Break-even, naive and complete, and lifetime cost.
- [Debt strategies](https://instead.fyi/#/debts): Avalanche, snowball and custom order with a cash-flow waterfall.
- [Prepay vs invest](https://instead.fyi/#/invest): Extra cash to the mortgage or to a portfolio.
- [Equity & sale](https://instead.fyi/#/equity): Home value, equity, LTV and net proceeds when selling.
- [Rent vs buy](https://instead.fyi/#/rent-vs-buy): Unrecoverable costs and net worth, not rent vs payment.
- [Return & risk](https://instead.fyi/#/returns): Cash flows, IRR, NPV, leverage and what a falling market would do.
- [Velocity banking](https://instead.fyi/#/velocity): The HELOC chunking strategy, measured against the benchmark it is never shown against.
- [Strategy Lab](https://instead.fyi/#/strategy-lab): Every allocation of your extra cash on one timeline.
- [Optimization explorer](https://instead.fyi/#/optimizer): Thousands of configurations, a Pareto frontier, no single score.
- [Sensitivity](https://instead.fyi/#/sensitivity): One variable across a range, everything else fixed.
- [Questions & glossary](https://instead.fyi/#/learn): Every term defined and every common question answered.
- [Data & settings](https://instead.fyi/#/settings): Import, export, reset, theme and assumptions.

## Questions answered

### Multiple debts
- Does velocity banking, the HELOC chunking strategy, actually work?
- What is the catch with using a line of credit against my mortgage?
- Avalanche or snowball, and why do they give different answers?
- Should the mortgage be part of my debt payoff plan?
- What is the rollover or snowball effect?
- What happens if I only pay the minimums?
- Why does the tool report a debt-free date and a mortgage-free date separately?

### The basics
- Why does a $300,000 loan at 6.5% over 30 years cost about $682,637?
- Why is my first payment almost entirely interest?
- Is my equity profit?
- What does amortization actually mean?
- What is the difference between the interest rate and the APR?
- Why does 6.5% not cost exactly 6.5% a year?
- Should I take a 15 year loan instead of a 30 year one?
- My equity chart goes up every month. Am I getting richer every month?

### Payments and prepaying
- Why is an extra payment early worth so much more than the same amount later?
- How much does one extra payment a year actually save?
- Do biweekly payments really save money?
- Will extra principal lower my monthly payment?
- I have a lump sum. Does it matter which month I apply it?
- Could I be penalized for paying early?
- Does it matter how I tell the servicer to apply an extra payment?

### Investing and returns
- Should I pay down the mortgage or invest the money?
- My house doubled in 30 years. Is that a good return?
- How does leverage amplify gains and losses?
- What does IRR mean for a home I live in, and why is it easy to misread?
- Why compute a return both with and without imputed rent?
- What return should I enter for investments?
- How does the tool handle taxes on investment gains?

### Refinancing
- What does break-even mean for a refinance, and why does this tool show two of them?
- How can a refinance with a lower monthly payment still cost me more?
- How do I tell whether a refinance is worth it?
- Should I roll the closing costs into the new loan?
- What does a cash-out refinance actually do to my position?

### Buying, selling and renting
- What happens to the numbers if my house does not appreciate at all?
- What if the house falls 20% in value?
- Are discount points worth paying?
- Do I need 20% down?
- When does PMI stop?
- What is actually inside closing costs?
- How much house can I afford?
- Is renting throwing money away?
- Why do my net proceeds look so much smaller than my equity?
- How much does my house have to appreciate just to break even?

### Method and honesty
- Why does the tool refuse to tell me which option is best?
- What does this tool deliberately not model?
- Why is there no Monte Carlo simulation?
- Why is the last payment different from all the others?
- How does the tool handle rounding?
- Is PMI included in the interest figures?
- Does this tool give financial advice?
- Why do my lender numbers differ slightly from these?
- Can I check these numbers myself?

### Using the tool
- Where is my data stored, and does anything leave my browser?
- How do I export and import my data?
- Why is the mortgage interest deduction off by default?
- Are the numbers adjusted for inflation?
- Why does no simulation ever spend my emergency reserve?
- What are scenarios for?
- What is the difference between the what-if page and the sensitivity page?
- What does the Strategy Lab do that the other pages do not?
- How does the optimizer search, and what does it return?

## Author

- [David Estévez](https://destbreso.com)