Same numbers, programmatically. This page runs entirely in the browser; the same engine is also available as a JSON API and MCP server (see llms.txt). The projection is a standalone, dependency-free script for Node or a browser: https://www.a3sec.net/tools/engines/retire-engine.js. Example: curl -sO https://www.a3sec.net/tools/engines/retire-engine.js && node -e "const R=require('./retire-engine.js');console.log(JSON.stringify(R.summarize(R.computeRetirement({currentAge:30,currentSavings:10000,monthlyContribution:500,retirementAge:65,lifeExpectancy:85,retirementMonthlyExpenses:3000,returnRatePct:7,inflationRatePct:3})),null,1))"
Prefill by URL: retire.html?age=30&savings=10000&contribution=500&retireAge=65&lifeExpectancy=85&expenses=3000&otherIncome=1800&return=7&tax=0&inflation=3&agent=1. Parameters: age, savings, contribution (per month), retireAge, lifeExpectancy, expenses (per month in retirement, today's dollars), otherIncome (Social Security, CPP/OAS, pensions per month from retirement, today's dollars), return (% per year), tax (capital-gains drag, %), inflation (%), mode (real|nominal), lang (en|uk), theme (dark|light); agent=1 opens this panel. Results appear below as JSON (element id resultsJson).
Model. After-tax return = return ร (1 โ tax), applied as an annual drag; real return = (1 + after-tax) / (1 + inflation) โ 1; monthly compounding with contributions added at the end of each month; nest egg needed = monthly expenses ร annuity-due factor over the months in retirement at the real monthly rate; sustainable income = projected nest egg รท that factor; drawdown withdraws expenses minus other income at the start of each month. A shortfall is shown with three separate fixes: the extra monthly saving that closes it exactly, the earliest retirement age that is on track, and the spending the plan supports. Contributions are constant in today's dollars and rise with inflation in nominal dollars. Nominal contributions sum the actual deposits; nominal gain/loss is the nominal nest egg minus those deposits. Other future values use (1 + inflation)^years. Currency-neutral.
No code execution? The same calculation is available as a JSON API (https://www.a3sec.net/api) and as MCP tools at https://www.a3sec.net/mcp. All three calculators are described in https://www.a3sec.net/llms.txt. Estimates only โ not financial advice.
Current results (JSON, updated on every change):
{}