Asset Allocation Tool

The calculator has two inputs. The result updates as soon as you change either one.

1. Your Age. Drag the slider to your current age. It runs from 25 to 80 and starts at 35. Use the age you are today, not the age you plan to retire, because the formula is keyed to age alone. Each year you move the slider to the right shifts one percentage point from stocks to bonds.

2. Risk Tolerance. Choose Conservative, Moderate, or Aggressive. Moderate is selected when the page loads; pick based on how you would behave in a downturn. Moderate uses the base formula with no adjustment; Aggressive adds 10 points of stocks, and Conservative removes 10 points.

Pick the setting based on how you behave, not how much you earn. Ask yourself what you did in the last big market drop, or what you would do if your balance fell by a third on paper. If you would keep contributing and leave the money alone, Aggressive may fit. If you would lose sleep or be tempted to sell, Moderate or Conservative is the more honest choice. If you have never invested through a downturn, it is reasonable to start with Moderate and revisit after you have.

3. Read the result. The ring and the two figures show your Stocks / Real Estate share (growth engines) and your Bonds / Cash share (safety net). Apply these percentages to your whole long-term portfolio across all of your accounts, not to each account separately. You can save the result to a free account and compare it with your actual holdings later.

The tool does not ask about your income, loans, pension, or retirement date. Treat its answer as a baseline, then adjust for those factors yourself.

Physicians often start investing seriously in their 30s, after medical school and residency, and frequently while still paying down student loans. Once you are an attending, your savings rate can be high, which means your contributions do much of the work in the early years. The question is less "how much risk can I squeeze in?" and more "what mix will I actually hold for the next 25 years?"

That is why a written plan matters. Decide your target mix and your rebalancing rule while markets are calm, and write them down. When stocks fall sharply, a plan you committed to in advance is what keeps you buying instead of selling at a loss. A busy clinical schedule makes this even more useful, because you will not have time to rethink your strategy in the middle of a downturn.

Your allocation also has to be spread across several account types: a 401(k) or 403(b), often a 457(b), a backdoor Roth IRA, sometimes after-tax 401(k) dollars through a mega backdoor Roth, an invested HSA, and a taxable brokerage account. The calculator gives you one mix for the whole portfolio. Deciding which account holds which piece is asset location, covered in our guide to investing your first $100K.

The calculator applies four steps, in this order:

1. Base stock share: 110 − age.
2. Risk adjustment: add 10 points for Aggressive, 0 for Moderate, subtract 10 for Conservative.
3. Limits: the stock share is held between 20% and 100%.
4. Bonds / Cash: 100 − stock share.

Because the slider only goes from 25 to 80, the limits never actually change a result. The highest output is 95% stocks (age 25, Aggressive) and the lowest is 20% stocks (age 80, Conservative). The glide path is a straight line: every year of age moves exactly one point from stocks to bonds, at every risk setting.

Stocks / bonds, in percent, as the calculator shows them.

That is the whole formula. The calculator does not project returns, run simulations, rebalance a portfolio, or factor in taxes or fees.

• Pearl: Treat the result as one mix for your whole household portfolio. Add up every long-term account, then check whether the combined stock and bond percentages match your target.
• Pearl: Write down your target and a rebalancing rule, either a calendar date or a drift band you set in advance. A rule you chose while markets were calm is easier to follow when they are not.
• Pearl: Rebalance with new money first. Directing contributions to whichever bucket is under target avoids selling, and in a taxable account, selling winners can trigger capital gains tax.
• Pitfall: Choosing Aggressive because your income is high. Income affects how much you can save, not how you will react when your balance drops. Selling after a crash can do more damage than a slightly lower stock share.
• Pitfall: Leaving new retirement contributions in cash. Uninvested cash in a new 401(k) or 403(b) counts toward the "Bonds / Cash" side, but it is rarely what you intended. If you are unsure what to pick, a target-date fund is a simple default.
• Pitfall: Treating a non-governmental 457(b) like your 403(b). Its assets stay the employer's property and are available to the employer's general creditors, so weigh that risk before counting on it as a core holding.