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

> @mount("ft4.burn")
operation burn(asset_ id: byte_ array, amount: big_ integer) Deletes tokens from an account's balance, decreasing the total supply by th

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.external.assets/burn/

OPERATION

# burn

```signature
@mount("ft4.burn")
operation burn(asset_id: byte_array, amount: big_integer)
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/external/assets/operations.rell#lines-118)

Deletes tokens from an account's balance, decreasing the total supply by the amount
being burned.

Must be signed by an auth descriptor with `accounts.auth_flags.TRANSFER`

Throws if the required assets cannot be burned. Common cases include:

* the account balance is lower than `amount`
* the amount to burn is not in the accepted range (0; 2^256) (exclusive)
* some conditions added in development through burn extensions (`before_burn` or
  `after_burn`) aren't met

**Parameters**

* **asset\_id** — id of the asset to burn
* **amount** — the amount of tokens to burn

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