Instantly see whether recent I‑Bond issues or short-term cash stand-ins are pulling ahead: this comparison tool loads TreasuryDirect’s full rate history, lets you stack multiple issuance cycles side by side, and even mixes in ETF/ETN tickers via live MyPlanIQ pricing data so you can evaluate fixed rates, cumulative gains, and CAGR curves across the exact start/end window you care about—all in one set of charts and summary stats.
I-Bond Comparison Tool
Compare the growth, cumulative gains, and annualized returns for multiple I-Bond issuances using the official TreasuryDirect rate history.
How to Use the I-Bond Comparison Tool
- Select at Least One I-Bond. Use the dropdown to pick the issuance you care about. Click “+ Add I-Bond” to insert more dropdowns (each removable) so you can compare multiple issue cycles. The default list starts with the most recent release.
- Enter the Investment Amount. Provide a whole-dollar value of $25 or more. This amount is used for each comparison (bonds and symbols) so their outputs are directly comparable.
- Choose Start and End Dates. These dates define the holding period for every item. The calculator snaps each date to the beginning of a month and enforces the 30-year I-Bond cap automatically.
- Add Extra Symbols (Optional). Enter ETF, Mutual Fund or even a stock ticker symbols (one per line) in the “Extra Symbols” textbox. Each symbol’s price history is pulled live from the MyPlanIQ pricing API and aligned to the same date window.
- Run the Comparison. Click “Compare Bonds.” The tool validates that you have at least two total entries (I-Bonds and/or symbols) and then computes projections, table rows, and charts.
Interpreting the Results
- Summary Table: Lists each item’s fixed rate (or “—” for symbols), start value, end value, cumulative return, and CAGR for the selected window.
- Growth Chart: Shows the account value trajectory for each entry, letting you spot divergence points between issue cycles or tickers.
- Returns Chart: Bar plot of cumulative % and CAGR % so you can rank the contenders quickly.
- Error Messages: Any missing data, invalid date ranges, or failed symbol fetches are reported directly above the table. Fix the highlighted issue and re-run.
Tip: Save your favorite symbol list and paste it back in whenever you revisit the calculator—caching ensures repeat symbols load faster.
How to use the I-Bond Comparison Calculator
The I-Bond Comparison Calculator is designed to help you pressure-test portfolio growth, compounding, drawdowns, income, and asset-allocation decisions across funds, stocks, and portfolios before you make a real-world change. Instead of relying on one rough estimate, run a few scenarios with conservative, base-case, and optimistic assumptions so you can see how sensitive the result is to returns, contribution levels, inflation, taxes, or timing.
A calculator result is most useful when you connect it to the account or plan decisions you actually control. After reviewing the output, compare it with your current savings rate, employer match rules, investment menu, expense levels, and withdrawal or rollover options. That is where MyPlanIQ's plan pages and retirement research become useful companions to the raw number.
If the result looks weak, treat that as a planning signal rather than a dead end. Small changes such as contributing earlier in the year, capturing the full company match, lowering fees, adjusting withdrawal assumptions, or choosing a more suitable allocation can materially change long-term outcomes. Re-run the calculator after each change and use the related links below to keep moving from estimate to action.
Related resources
- See plan investment menus and ratings
- Read more about investment portfolio decisions
- Explore all calculators
- Portfolio Calculator Simulator
- Dollar Cost Average Calculator
- Investment Comparison Calculator
Calculator FAQs
What is the best way to compare investment scenarios?
Keep the time horizon the same, change only one major assumption at a time, and compare total return, drawdown, income, and ending value together. That keeps the comparison focused and easier to trust.
Why do fees and allocation matter in portfolio calculators?
Even modest fee differences or allocation changes compound over long periods. A portfolio calculator helps you see how those seemingly small choices can change long-term wealth and income.
How should you use a portfolio result in your retirement planning?
Use the result to review whether your workplace plan menu, fund costs, and asset mix support the growth or income path you want. Then test another related calculator to pressure-test the decision.