Use the I Bond Calculator to get monthly values of your I bond investment. Get a graphical comparison of your I bond's growth to inflation. Download monthly values in CSV format.
Start hereIf you hold I bonds for five years or more, you'll receive the full interest when you redeem them. As of October 1, 2024, there are 254 I bonds that are older than five years, purchased between September 1998 and October 2019. Out of these, 217 will provide a real return if redeemed in October, meaning their values have increased beyond their inflation-adjusted purchase prices. The remaining 37 have not kept pace with inflation. The I bond purchased in May 2000 boasts the highest return at 143.52%, while the February 2015 purchase shows the lowest return at -2.19%.
The chart below illustrates the growth of I bonds purchased monthly from September 1998 to October 2019, compared to inflation during the same period. The variance depicted in the graph represents the difference between the bond value and the inflation-adjusted purchase price as of 10/1/2024, expressed as a percentage of that adjusted price. This reflects the cumulative real growth from the purchase date to 10/1/2024, rather than annual growth.
For instance, as of 10/1/2024, a $10,000 I bond bought in September 1998 had increased by 141.60% compared to its inflation-adjusted purchase price.
Use the Next and Previous buttons to move around the purchase dates of bonds.
The chart below illustrates the number of I bonds older than five years in relation to their inflation-adjusted purchase prices from January 2020 to October 2024. For instance, in January 2020, there were 196 I bonds over five years old, with 193 surpassing their inflation-adjusted purchase prices and only three falling below that threshold.
In contrast, by October 2024, out of 254 I bonds older than five years, 217 (85%) exceeded their inflation-adjusted purchase prices, while 37 were below.
Click on a legend to toggle a dataset.
Use this tool to generate a table summarizing all your I bonds as of the first of the current month. The table will list out the following information:
An additional column will contain a link to the details of the individual I bonds. A copy button makes it easy to copy and paste the generated table into Microsoft Excel or other applications.
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