Treasury TIPS Real Yield Calculator
Calculate the composite return, real yield, nominal yield, and inflation-adjusted principal of Treasury Inflation-Protected Securities (TIPS) using the official composite rate formula.
What Are Treasury TIPS and How Do They Work?
Treasury Inflation-Protected Securities (TIPS) are US government bonds where the principal automatically adjusts based on changes in the Consumer Price Index (CPI). If CPI rises 3%, a $10,000 TIPS becomes $10,300 in principal. Your coupon (fixed rate) is paid on this adjusted principal, so both your interest payments and your final repayment are inflation-protected. TIPS are issued with 5-, 10-, and 30-year maturities and are available through TreasuryDirect.gov and on secondary markets. Source: SEC.gov Investor Bulletin on TIPS. Last updated: May 2026.
TIPS Composite Return Formula
The TIPS composite return is not a simple addition of fixed rate + CPI. The correct formula is: Composite = (1 + fixed rate) × (1 + CPI rate) − 1. At a 2% fixed rate and 3.2% CPI, the composite is (1.02 × 1.032) − 1 = 5.264%, not the simple-sum 5.2%. This cross-product term matters more at higher inflation rates. The calculator above uses the exact formula.
| Fixed Rate | CPI Rate | Simple Sum | Correct Composite | Difference |
|---|---|---|---|---|
| 2.0% | 3.0% | 5.00% | 5.06% | +0.06% |
| 2.0% | 5.0% | 7.00% | 7.10% | +0.10% |
| 2.0% | 8.0% | 10.00% | 10.16% | +0.16% |
TIPS vs Nominal Treasuries vs I-Bonds
Nominal Treasuries pay a fixed nominal yield — if inflation beats that yield, your real return is negative. TIPS guarantee a positive real return as long as CPI is measured correctly. I-Bonds also use the composite formula but have a $10,000/year purchase cap and are non-tradeable. TIPS are better for large institutional allocations, laddering strategies, and retirement accounts where phantom income tax on CPI adjustments is deferred. The breakeven inflation rate — where TIPS and nominal Treasuries produce the same nominal return — is a key market signal watched by the Federal Reserve.
Frequently Asked Questions
What are Treasury TIPS?
Treasury Inflation-Protected Securities (TIPS) are US government bonds where the principal adjusts with inflation (CPI). You earn a fixed real interest rate on the inflation-adjusted principal. Source: TreasuryDirect.gov and SEC.gov.
How is TIPS composite return calculated?
The TIPS composite return = (1 + fixed rate) × (1 + CPI rate) - 1. For example, a 2% fixed rate and 3% inflation gives (1.02 × 1.03) - 1 = 5.06% nominal return.
Are TIPS taxed on the inflation adjustment?
Yes. The CPI-based principal adjustment is taxable as ordinary income each year, even though you don't receive the cash until maturity. This phantom income tax makes TIPS best held in tax-advantaged accounts. Source: IRS Publication 550.
What is a good real yield on TIPS?
A positive real yield above 1.5-2% is historically considered attractive. As of early 2026, 10-year TIPS real yields were near 2.0-2.3%, meaning you earn that above CPI inflation.
TIPS vs I-Bonds — which is better?
I-Bonds have a $10,000/year purchase limit but no secondary market risk. TIPS have no purchase limit, trade on secondary markets, and can have negative real yields if bought at a premium. TIPS are better for large allocations.