# derive_nonce · FT4 Rell API · Chromia Docs (concept)

> function derive_ nonce(op: gtx_ operation, nonce: integer): text A utility function that computes a unique nonce for this operation's message to sign. Para

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.utils/derive_nonce/

FUNCTION

# derive\_nonce

```signature
function derive_nonce(op: gtx_operation, nonce: integer): text
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/utils/utils.rell#lines-49)

A utility function that computes a unique nonce for this operation's message to sign.

**Parameters**

* **op** — the operation to be signed
* **nonce** — starting from 0, it will be increased on every operation performed by the same auth descriptor. 0 if the signer is creating a new auth descriptor

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/lib.ft4.utils/derive_nonce.html)Generated API reference, mirrored from the live docs