Developers.

Free API and widget. No key needed. CORS enabled. Fair-use limits per IP: search 60/min (smart 20/min), code lookups 120/min. Please cache on your side and link back.

embed the search widget

<div id="findmyhsn-widget"></div>
<script src="https://findmyhsn.com/widget.js" async></script>

search api

GET https://findmyhsn.com/api/v1/search?q=steel+water+bottle&mode=smart

{
  "query": "steel water bottle",
  "mode": "smart",
  "results": [
    {
      "code": "961700",
      "type": "HSN",
      "description": "VACUUM FLASKS AND OTHER VACUUM VESSELS...",
      "plain_description": "...",
      "gst": { "igst": 18, "cgst": 9, "sgst": 9,
               "notification_no": "9/2025-Central Tax (Rate)",
               "effective_from": "2025-09-22" },
      "confidence": 0.86,
      "url": "https://findmyhsn.com/hsn/961700"
    }
  ],
  "disclaimer": "Reference information, not tax advice..."
}

mode=fast is keyword-only and fastest; mode=smart adds AI re-ranking for descriptive queries.

code lookup api

GET https://findmyhsn.com/api/v1/codes/85171300

{
  "code": "85171300",
  "type": "HSN",
  "level": "tariff_item",
  "official_description": "SMARTPHONES",
  "gst_rates": [{ "igst": 18, "cgst": 9, "sgst": 9,
                  "notification_no": "9/2025-Central Tax (Rate)",
                  "effective_from": "2025-09-22" }],
  "children": [],
  "url": "https://findmyhsn.com/hsn/85171300"
}

Rates carry their source notification and effective date — surface both to your users. Attribution appreciated: link to the code page you display. Questions or higher limits: contact us.