---
title: nonce
framework: storekit
role: symbol
role_heading: Instance Property
path: storekit/skpaymentdiscount/nonce
---

# nonce

A universally unique ID (UUID) value that you define.

## Declaration

```swift
var nonce: UUID { get }
```

## Discussion

Discussion Your server generates a unique nonce when it creates the signature string for the payment discount. The string representation of the nonce must be lowercase. You can use a nonce one time; generate a new one for every buy request.

## See Also

### Validating the Discount

- [signature](storekit/skpaymentdiscount/signature.md)
- [timestamp](storekit/skpaymentdiscount/timestamp.md)