Starting tool
Monthly Budget Calculator
Build a detailed household budget and see surplus, shortfall, and allocation against custom targets.
ResultCash-flow summary, category breakdown, and allocation charts
- Monthly breakdown
- Cash-flow summary
Financial tool index
Personal finance calculators
Choose the planning tool that matches your next financial decision. Each calculator turns your inputs into concrete breakdowns, projections, comparisons, or schedules.
10 calculators 5 planning stages Detailed results
Complete directory
Browse all calculators
Choose a PlanArith calculator for budgeting, net worth, debt, savings, retirement, financial independence, or life insurance planning.
01 · Understand
Financial baseline
Start with monthly cash flow and the balance sheet you have today.
Starting tool
Net Worth & Projection Calculator
Calculate assets minus liabilities, then model growth, debt payments, and purchasing power.
ResultCurrent snapshot, asset and liability detail, and three projections
- Asset and liability breakdown
- Scenario projections
02 · Stabilize
Debt and stability
Build a reserve, choose a payoff order, or compare consolidation costs.
Emergency Fund Calculator
Inflation-adjusted target, time to fund, and stress-scenario drawdown- Emergency fund target
- Savings projection
Debt Payoff Calculator
Strategy comparison, interest estimates, and a monthly payoff schedule- Strategy comparison
- Payoff schedule
Debt Consolidation Calculator
Side-by-side costs, payment change, break-even APR, and schedules- Cost comparison
- Break-even APR
03 · Build
Savings and major goals
Translate a future savings or education target into a funded path.
04 · Plan
Retirement and financial independence
Test retirement income coverage or a financial-independence timeline.
Long-range model
Retirement Readiness Calculator
Model accounts, employer contributions, retirement income, funding gaps, and longevity.
Result
Required-versus-projected portfolio, scenarios, and income coverage
- Portfolio projection
- Income coverage
Long-range model
FIRE Calculator
Estimate Lean, Base, and Fat FIRE targets, an FI date, funding gap, and Coast FIRE.
Result
Three FIRE scenarios, target-age projection, and monthly schedule
- FIRE target
- FI timeline
05 · Protect
Protection
Estimate the resources a household may need after an income loss.
Life Insurance Needs Calculator
Needs breakdown, additional coverage estimate, and scenario comparison
- Coverage breakdown
- Scenario comparison