Hledger-interest is a small command-line utility based on Simon Michael's hledger library. Its purpose is to compute interest for a given ledger account. Using command line flags, the program can be configured to use various schemes for day-counting, such as act/act, 30/360, 30E/360, and 30/360isda. Furthermore, it supports a (small) number of interest schemes, i.e. annual interest with a fixed rate and the scheme mandated by the German BGB288 (Basiszins für Verbrauchergeschäfte). Extending support for other schemes is fairly easy, but currently requires changes to the source code.