Sharpe Ratio Calculator

How to use this calculator

Enter the Portfolio Return (annual return in %), the Risk-Free Rate (use the current 3-month T-bill or 10-year Treasury yield), and the Standard Deviation (annualized volatility of the portfolio’s returns).

The calculator returns:

• Sharpe Ratio: the primary risk-adjusted return metric
• Excess Return: return above the risk-free rate
• Return per Unit of Risk: same as Sharpe ratio, reframed

The Sharpe ratio formula

Where:

• Rp = Portfolio return (annualized)
• Rf = Risk-free rate (3-month T-bill or relevant short-term rate)
• σp = Portfolio standard deviation (annualized)

The numerator (Rp − Rf) is the “excess return,” what the investor earned above what a risk-free investment would have paid. The denominator (σp) is the “price” of that excess return in terms of volatility endured.

Higher Sharpe = more return per unit of risk = better risk-adjusted performance.

Sharpe ratio interpretation guide

Sharpe Ratio	Interpretation
Below 0.0	Poor; underperformed the risk-free rate on a risk-adjusted basis
0.0–0.25	Very poor; almost certainly worse than passive investing
0.25–0.50	Below average; market returns without market efficiency
0.50–1.00	Average to good; typical range for equity strategies
1.00–1.50	Very good; uncommon for diversified strategies
1.50–2.00	Excellent; rare at scale, may indicate niche edge
Above 2.00	Exceptional; verify data, often unsustainable or model-fit

Historical reference points:

• S&P 500 (long-run): ~0.40–0.50
• Classic 60/40 portfolio: ~0.55–0.65
• Warren Buffett / Berkshire Hathaway (multi-decade): ~0.76
• Well-managed hedge funds: 0.80–1.20
• Madoff (fraudulent, claimed): 2.5+, a red flag in retrospect

A Sharpe ratio above 2.0 should trigger skepticism, not celebration. Either the strategy is operating in a very narrow inefficient niche, or the data was cherry-picked. Legitimate diversified strategies rarely sustain Sharpe ratios above 1.5 over long periods.

How to find standard deviation for your portfolio

Standard deviation measures how much the portfolio’s returns vary from the average. Here’s how to calculate it:

1. Collect monthly returns for 36–60 months (longer = more reliable)
2. Calculate the average monthly return
3. Compute the variance: average of squared differences from the mean
4. Take the square root for monthly standard deviation
5. Annualize: multiply by √12 (approximately 3.464)

Reference: Standard deviations by asset class:

Asset Type	Approx. Annual SD
Cash / money market	0.5–1%
Investment-grade bonds	5–8%
Balanced 60/40	10–12%
U.S. large-cap equity (S&P 500)	14–18%
U.S. small-cap equity	18–25%
Emerging markets equity	22–30%
Individual stocks	25–60%+
Crypto assets	60–100%+

Most fund fact sheets publish the standard deviation directly (often labeled “volatility” or “risk”). Use that figure rather than calculating manually.

Why two funds with identical returns can have very different risk profiles

Two funds both returned 12%. Which is better?

Fund	Return	Risk-Free Rate	Standard Deviation	Sharpe Ratio
Fund A	12%	5%	8%	0.875
Fund B	12%	5%	20%	0.350

Fund A is clearly superior; it produced the same return with 60% less volatility. An investor in Fund A could have used moderate leverage to amplify the low-volatility return and achieve a higher absolute return at the same risk level as Fund B.

This is the core insight of the Sharpe ratio: return without context is meaningless. The relevant question is always how much risk was taken to earn it.

Limitations of the Sharpe ratio

The Sharpe ratio has real weaknesses:

1. Penalizes upside volatility equally with downside. A fund that has occasional 30% gain months looks riskier under Sharpe than one with steady 1% monthly returns, even when the big gains are desirable. The Sortino ratio fixes this.

2. Assumes normal distribution. Real return distributions have fat tails; extreme events are more frequent than the normal distribution predicts. The Sharpe ratio can look excellent for a strategy that earns steady gains but occasionally blows up catastrophically (e.g., writing naked options).

3. Sensitive to the choice of risk-free rate. Changing Rf from 2% to 5% significantly changes the ratio when excess returns are small.

4. Not comparable across different time frames without annualization. A monthly Sharpe of 0.3 is not the same as an annual Sharpe of 0.3. Annualize both: Monthly × √12.

Sharpe ratio vs. other risk-adjusted metrics

Metric	Denominator	Best For
Sharpe Ratio	Total standard deviation	General risk-adjusted comparison
Sortino Ratio	Downside standard deviation	Asymmetric strategies, trend-following
Treynor Ratio	Beta (systematic risk)	Evaluating contribution to a diversified portfolio
Calmar Ratio	Maximum drawdown	Trend-following, futures strategies
Information Ratio	Tracking error vs. benchmark	Active fund managers

Use Sharpe for general portfolio performance comparison. Use Sortino when upside volatility is significant. Use Calmar for trend-following or drawdown-sensitive investors.

The bottom line

The Sharpe ratio answers the most important question in investment analysis: “How much risk did you take to earn that return?”

A fund or strategy is only genuinely good if its Sharpe ratio exceeds what was available in passive alternatives. For the U.S. equity market, the long-run Sharpe is approximately 0.45. Any active strategy should clear that bar before its fees are counted, and most don’t.

Use this calculator to:

1. Compare two investments on an equal footing
2. Screen fund managers for skill vs. luck
3. Evaluate whether the risk in your portfolio is being adequately compensated

For a version that only penalizes harmful downside volatility, use the Sortino Ratio Calculator.