> For the complete documentation index, see [llms.txt](https://docs.faspay.co.id/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.faspay.co.id/merchant-integration/api-reference-1/credit-card-transaction/additional-api-integration/untitled/generate-signature-request.md).

# Generate Signature Payment API

Signature transaction is a security feature that allows the merchant to identify the transaction script from faspay system

The signature for tokenization registration API generated by these steps:

1. stringToSign = "##" + strings.ToUpper(username)  + "##" + strings.ToUpper(password) + "##" + strings.ToUpper(merchant\_tranid) + "##" + amount + "##" + "0" + "##"
2. hash sha256 stringToSign in binary
3. encode to base64

**Sample Generate Signature :**

stringToSign = "##" + "MPGS\_PURCHASE" + "##" + "ABCDE" + "##" + "TKN106" + "##" + "10000.00" + "##" + "0" + "##"