Show HN: OpenTaxRate – open-source US sales tax rates by street address

I built this because I tried many sales tax APIs and the problems were: a) the rates were a black box with no source attached b) lookups resolved by ZIP code. ZIP codes are postal routes, not tax jurisdictions. Stripe's Tax team wrote a good post on this [1]: two houses in Drexel, MO share a city, a ZIP, and nearly a house number, but sit in different counties with different rates. If your lookup key is the ZIP, you are wrong on those addresses, even when the rate table is accurate. OpenTaxRate resolves the street address instead: - SST member states (24): the quarterly rate + boundary files, street ranges and ZIP+4, not just the rate tables - Non-SST states: a custom adapter for each state, using its DOR's own published tables and boundary files (TX Comptroller, FL DR-15DSS, ALDOR, IDOR,