Grant discovery platforms are a quiet SaaS category with remarkable pricing: $179 to $459 a month for keyword alerts on grant opportunities. The primary source for US federal grants is grants.gov, and it has a public JSON API with no key, no registration, and no rate-limit drama. Here is the whole thing.

Search is one POST

POST https://api.grants.gov/v1/api/search2

Content-Type: application/json

{