Skip to content

Retirement, FIRE, debt and cash reserves

Four deeper calculators for retirement, independence, debt and cash reserves

The home portal covers compound interest, a single-debt payoff and a savings-gap check. This page goes further: a retirement shortfall, a FIRE Index, a multi-debt snowball and an emergency-fund size that fits household risk.

Choose a calculator Read the matching guides

Pick the question you actually need answered

Jump into any calculator, change the inputs, and watch the projection update instantly.

Retirement Gap

Will today’s path fund the income you want, after inflation and other income?

Open Retirement Gap

FIRE Index

What share of your independence number do you already hold, and how many years remain?

Open FIRE Index

Debt Snowball

Clear several balances, roll payments forward and see interest and time saved.

Open Debt Snowball

Emergency Fund

Size a cash reserve from essential costs, income stability and household risk.

Open Emergency Fund
Inputs stay in your browser. Nothing you type is uploaded.

How to read any result on this page

The number on the right is only as honest as the assumptions on the left. Treat every output as a planning estimate, then test a cautious case and an optimistic case before you change a contribution or a payment.

  1. 1

    Enter figures you can defend

    Use balances, payments and spending from recent statements, not round numbers you hope are close enough.

  2. 2

    Change one lever at a time

    Move saving, timeline or return separately so you can see which adjustment is realistic for your household.

  3. 3

    Read the notes under the chart

    Each calculator states compounding frequency, inflation treatment and what is left out, including tax and fees.

Calculator 1 of 4

Retirement Gap

Project the portfolio you may have at retirement, compare it with the capital needed to fund inflation-linked income after pensions, and see the extra monthly saving that would close the gap.

Calculator 2 of 4

FIRE Index

Express your invested portfolio as a share of the amount that would cover yearly spending at a chosen withdrawal rate. The index, lean and fat variants, and years-to-independence all use today’s money.

Calculator 3 of 4

Debt Snowball

List several debts, add an extra payment and watch the smallest balance clear first. Freed-up minimums roll into the next account. Compare the result with paying only the minimums.

Calculator 4 of 4

Emergency Fund

Start from essential monthly costs, then raise the cover for variable income, a single earner, dependants and thinner insurance. The target is a cash reserve, not an investment plan.

What every model on this page assumes

Shared rules keep the four tools comparable. The About page documents the full method if you want the formulas.

Constant rates

Returns, inflation and interest are held steady so you can isolate one input at a time.

Monthly steps

Growth, contributions and debt interest are applied monthly, which matches most household cash flow.

No tax or fees

Tax, product charges and market volatility are omitted. Lower the return if you want a more cautious case.

Private by design

Figures never leave this device. Reset a form to start over with fresh inputs.

After the number, read the idea behind it

Calculators measure a gap. The guides show which household decisions usually close it.

Retirement gap guide

Work in today’s money and test one assumption at a time.

Open the guide

FIRE spectrum

Lean, standard, fat and coast targets are not the same number.

Open the guide

Snowball versus avalanche

One order saves interest; the other builds early wins.

Open the guide

Sizing an emergency fund

Cover essentials only, then raise the buffer for income risk.

Open the guide