# sum

[Built-ins](README.md) · [Labs guide](../guides/labs.md)

Canonical ID: `math.sum`. Nederlands: `som`.

Adds a List of finite Numbers from left to right. An empty List sums to zero.

## Signature

```text
sum(numbers)
```

## Return value and behavior

Number; an intermediate overflow is an error.

Numeric lists contain at most 4096 finite Numbers; invalid items are rejected.

## Example

```pliro
# language: en
say sum([1, 2, 3])
```