Sharpe Ratio Calculator

As a general benchmark:

• Sharpe ratios below 0 indicate the investment underperforms the risk-free rate — you would be better off in Treasury bills.
• Ratios of 0 to 0.5 are subpar.
• 0.5 to 1.0 are acceptable.
• 1.0 to 2.0 are good.
• above 2.0 are excellent (and rare for sustained periods).

The S&P 500's long-term Sharpe ratio is approximately 0.4-0.5, meaning broad market returns barely exceed what risk alone would predict.

Warren Buffett's Berkshire Hathaway has achieved a Sharpe ratio of approximately 0.79 over 50+ years — seemingly modest but remarkable for its consistency.

Hedge funds claiming Sharpe ratios above 3 often have short track records, survivorship bias, or strategies with hidden tail risks not captured by standard deviation.

As the CFA Institute notes, the Sharpe ratio assumes returns are normally distributed, which fails for strategies with skewed returns — options selling strategies often show high Sharpe ratios until a tail event causes catastrophic losses.

It penalizes upside volatility equally with downside volatility, which is counterintuitive since investors welcome upside surprises. The Sortino ratio addresses this by using only downside deviation.

Time period selection significantly affects results: many funds looked excellent on a 2009-2021 Sharpe basis but poor when including 2022. Comparing Sharpe ratios across different time periods or asset classes requires caution.

Additionally, leveraged strategies can artificially inflate Sharpe ratios — a 2x leveraged S&P 500 fund has approximately the same Sharpe as the unlevered index despite double the returns and double the volatility.

Modern portfolio theory — the framework by Nobel laureate Harry Markowitz — uses the Sharpe ratio to find the optimal portfolio on the efficient frontier — the combination of assets that maximizes the Sharpe ratio is called the tangency portfolio.

In practice, investors use it to evaluate whether adding an asset improves portfolio efficiency. An asset with a lower standalone return but low correlation to existing holdings can increase the portfolio Sharpe ratio through diversification.

For example, adding international bonds (4% return, 5% volatility, 0.2 correlation to US stocks) to a pure US equity portfolio typically improves the Sharpe ratio despite lower absolute returns.

The formula for portfolio Sharpe improvement considers both individual asset Sharpe ratios and their correlation — uncorrelated assets with moderate Sharpe ratios often add more value than highly correlated assets with high Sharpe ratios.

The Sharpe ratio is (Portfolio Return − Risk-Free Rate) ÷ Standard Deviation of Returns.

If a fund returns 12%, the risk-free rate is 4%, and its volatility is 10%, the Sharpe ratio is (12 − 4) ÷ 10 = 0.8.

It measures how much excess return you earn for each unit of risk taken, letting you compare investments with very different volatility on a level field.

The Sharpe ratio penalizes all volatility, including upside swings that investors actually welcome.

The Sortino ratio fixes this by dividing excess return only by downside deviation, measuring return per unit of harmful risk.

For asymmetric or option-like strategies, Sortino often gives a fairer picture, while Sharpe remains the universal benchmark for broadly diversified portfolios.

Where Sharpe divides excess return by total volatility (standard deviation), the Treynor ratio divides it by beta — systematic, market-related risk only.

Treynor is appropriate when an investment sits inside an already-diversified portfolio, so only market risk matters.

Use Sharpe to judge a standalone portfolio and Treynor to judge a component of a larger one.

The risk-free rate is usually the yield on a short-term government security such as the 3-month US Treasury bill, matched to your measurement period.

Using a rate that is too high understates the Sharpe ratio and vice versa.

For consistency, apply the same risk-free rate across every investment you compare, and update it as prevailing rates change.

Sharpe ratios are usually quoted annually so they can be compared across funds.

To annualize a Sharpe computed from monthly data, multiply by the square root of 12; for daily data, multiply by the square root of about 252 trading days.

Always confirm whether a reported Sharpe is monthly or annualized before comparing, since the difference is roughly 3.5x for monthly figures.

As a rough guide:

• a Sharpe ratio below 1 is considered subpar.
• 1–2 is good.
• 2–3 is very good.
• above 3 is excellent.

Most long-only equity portfolios land between 0.5 and 1 over full market cycles.

Be skeptical of unusually high Sharpe ratios from short track records — they often reflect luck, leverage, or hidden tail risk rather than genuine skill.

For highly volatile assets like cryptocurrency, the Sharpe ratio can be misleading because returns are far from normally distributed and suffer sudden crashes.

A high Sharpe during a bull run can mask catastrophic downside risk.

When evaluating crypto, pair Sharpe with the Sortino ratio and maximum drawdown to avoid being lured by a flattering risk-adjusted number.

An ex-post Sharpe ratio is calculated from realized historical returns, while an ex-ante Sharpe uses expected returns and forecast volatility for a forward-looking estimate.

Backtested ex-post figures describe the past and can be over-optimized; ex-ante figures depend entirely on the quality of your assumptions.

Treat any single Sharpe number as one data point, not a guarantee of future performance.

Typical errors include:

• mixing time frames (comparing a monthly Sharpe to an annualized one).
• using an outdated risk-free rate.
• trusting a high ratio from a short or cherry-picked period.

The Sharpe ratio also assumes roughly normal returns, so it underestimates the risk of strategies with fat tails.

Use it as one lens among several, never as a sole decision metric.