> For the complete documentation index, see [llms.txt](https://docs.xplorpay.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.xplorpay.com/api-reference/api/payments/cards-card-not-present/hpp-signature-verification.md).

# HPP signature verification

The **HPP signature verification** service allows you to verify the digital signature of a transaction webhook without implementing signature verification in your own application. The service accepts the complete transaction webhook payload and uses the terminal public key provided in the request to verify the webhook signature.

Use this service when you prefer a hosted verification option instead of implementing local signature verification.

To verify a transaction webhook:

* Receive the transaction webhook from the Xplor Pay.
* Send the complete webhook payload to the HPP Signature Verification Service.
* Include the terminal public key in the `public-key` request header.
* The service verifies the webhook signature.
* Check the verification response to determine whether the signature is valid.

Related topics:

* [Transaction Webhooks](https://docs.xplorpay.com/api-reference/webhooks/working-with-webhooks/transaction-webhooks)
* [Transaction Alert Settings](https://docs.xplorpay.com/api-reference/api/payments/gateway-settings#transaction-alert)


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