The `decimal_sum()` SQL function is available (as an extension) in the [prerelease snapshot][1]. That function does unlimited-precision decimal arithmetic. It returns an exact answer. The decimal_sum() function uses more CPU cycles than sum(), obviously. The decimal_sum() function is built into the CLI in the prerelease snapshot But in order to use it in your applications, you will have to load it as an extension. [1]: https://sqlite.org/download.html