Alpha Beta Calculator
Calculate investment portfolio Alpha (α) and Beta (β) to measure risk-adjusted performance vs market benchmark.
Enter monthly/quarterly/annual returns (same period as market)
Use S&P 500 or relevant index (must match portfolio periods)
2025: 10-Year Treasury ~4.5%, 3-Month T-Bill ~5.3%
Performance Metrics
⚠️ Higher volatility than market
✅ Outperforming risk-adjusted expectations
Interpretation:
Your portfolio has a beta of 1.33 (33% more volatile than market) and generated +0.77% alpha (outperformance) after risk adjustment.
How to use:
- Enter portfolio returns for past 12-36 months (comma-separated)
- Enter market benchmark returns for same periods (e.g., S&P 500 for US stocks)
- Set risk-free rate (2025: 10Y Treasury ~4.5%, 3M T-Bill ~5.3%)
- Beta measures volatility vs market; Alpha measures skill/outperformance
About This Calculator
Calculate stock alpha (excess returns) and beta (market risk) for portfolio analysis. Compare against S&P 500 benchmark with risk-adjusted performance metrics. Evaluate fund managers and optimize portfolio allocation based on alpha/beta ratios in 2025.
Frequently Asked Questions
What is alpha in investing?
Alpha measures investment performance relative to a benchmark index (usually S&P 500), representing excess returns after adjusting for market risk. Positive alpha (+3%) means the investment beat the market by 3% after accounting for risk, while negative alpha (-2%) means it underperformed by 2%. Alpha reveals manager skill鈥攁 fund with +5% alpha consistently demonstrates superior stock selection or timing, while 0% alpha indicates no added value beyond index fund performance. Calculated as: Actual Return - (Risk-Free Rate + Beta 脳 Market Risk Premium).
What is beta and how does it measure risk?
Beta measures a stock's volatility relative to the overall market (S&P 500 = beta of 1.0). Beta > 1.0 (e.g., 1.5) means the stock is 50% more volatile than the market鈥攊f S&P rises 10%, stock tends to rise 15%; if S&P drops 10%, stock drops 15%. Beta < 1.0 (e.g., 0.7) indicates 30% less volatility鈥攄efensive stocks like utilities often have beta 0.5-0.8. Beta = 0 means no correlation to market (e.g., gold sometimes). High beta stocks (1.2-2.0) offer higher return potential but greater downside risk during corrections.
How do I use the Alpha Beta Calculator?
Enter your values in the input fields provided, and the calculator will automatically compute results in real-time. Start with the required fields (marked with labels), then adjust optional parameters to fine-tune your calculation. Results update instantly as you change inputs, allowing you to quickly compare different scenarios. For the most accurate results, use precise figures from official documents rather than rough estimates. If you are unsure about any input, hover over the field label for a brief explanation of what value to enter.
How accurate are the results from the Alpha Beta Calculator?
This calculator uses standard industry formulas and up-to-date 2025 data to provide reliable estimates. Results are most accurate when you input precise, verified figures. Keep in mind that calculators provide estimates based on mathematical models — real-world outcomes may vary due to factors not captured in the inputs, such as market changes, policy updates, or individual circumstances. For high-stakes decisions, use these results as a starting point and consult with a relevant professional (financial advisor, doctor, engineer, etc.) for personalized guidance.
Can I save or share my Alpha Beta Calculator results?
You can bookmark this page or take a screenshot of your results for future reference. To share results with others, copy the page URL — your specific inputs are not stored in the URL for privacy reasons, so the recipient will need to enter their own values. For record-keeping purposes, we recommend noting your inputs and results in a spreadsheet or document. This allows you to track changes over time and compare different scenarios side by side.