Finance Tools
What It Does
Suggests a target stocks / bonds / cash split based on your age, target retirement age, and risk profile, using one of four well-known approaches: the classic 100 − age rule, the slightly more aggressive 110 − age, the modern 120 − age, or a smooth target-date-fund-style glide path. Also lets you specify a fully custom split. Optionally shows the result in dollar amounts for a portfolio you enter, compares all four strategies side-by-side, and projects how your allocation should drift in 5-year intervals through retirement and 30 years beyond.
How to Use It
- Enter your current age and target retirement age.
- Pick a risk profile: Conservative, Moderate, Aggressive, or Custom.
- If not Custom, choose an allocation strategy. Optionally override the default cash sleeve (5 % for Moderate).
- If Custom, enter your own Stocks / Bonds / Cash percentages — they must sum to 100.
- Optionally enter your portfolio value to see dollar amounts per asset class.
- Click “Calculate” to see today’s recommended allocation, the strategy comparison, and the glide-path projection.
- Use “Copy Results” to copy everything, or “Export CSV” / “Export Excel” to save the analysis.
Options Explained
| Option | Description |
|---|---|
| Risk profile | Shifts the rule’s stock allocation by ±10 pp. Conservative leans toward bonds + cash; Aggressive leans toward stocks. Custom unlocks a manual split |
| Allocation strategy | Four built-in approaches. The “N − age” rules give a stock % equal to N minus your age. Target-date is a smooth linear glide path |
| Cash sleeve | Carved out before the stock/bond split. Profile defaults: Conservative 10 %, Moderate 5 %, Aggressive 0 %. Cap is 30 % |
| Custom split | Enabled when risk profile = Custom. Enter your own three percentages — they must sum to 100 |
| Portfolio value | Optional. When > 0, the result includes dollar amounts. Currency is for display only — no FX conversion |
| Glide-path step | Always 5 years. Projection runs from your current age to retirement + 30 years (capped at age 120) |
Example
At 35 with a Moderate profile and the 110 − age rule, the result is 75 % stocks / 20 % bonds / 5 % cash. With a $100,000 portfolio that translates to $75,000 / $20,000 / $5,000. By age 65 (retirement) the same rule recommends 45 % stocks; by 95, 15 %.
Tip
The “rules of thumb” are starting points, not prescriptions. Two 35-year-olds can have very different right answers depending on income stability, debts, dependents, insurance, and tax situation. Use the comparison table to see how much the choice of rule actually moves the needle for your portfolio — often less than people think over a 30-year horizon, because the glide path itself does most of the work.
About Glide Paths and the “N − age” Rules
Asset allocation drives the majority of a long-term portfolio’s return and its volatility. The classic insight is that as you age, your time horizon for any new investment shrinks — and so should the share of volatile assets (stocks) in the portfolio. The simplest expression of this is the “100 − age” rule: a 30-year-old holds 70 % stocks; a 70-year-old holds 30 %. Decades of declining bond yields and longer lifespans pushed practitioners toward 110 − age and even 120 − age variants, which keep more in stocks for longer.
Modern target-date funds replace the linear rule with a smooth glide path — typically starting around 90 % stocks for 25-year-olds and tapering to 30–40 % stocks at retirement, with continued de-risking through the first decade of retirement. None of these formulas account for income, debts, or risk tolerance, which is why a risk-profile shift (Conservative −10 pp, Aggressive +10 pp) and a cash sleeve (typically 0–10 % for a liquidity buffer) are useful overlays on top of any chosen rule. The right answer for any individual is almost always somewhere between two of these; the comparison table makes the trade-offs explicit.
Disclaimer: These rules of thumb are educational starting points, not personalized investment advice. Your ideal allocation depends on your full financial picture — consult a qualified advisor before making investment decisions.