# set_block_interval · Rell standard library · Chromia Docs (concept)

> function set_ block_ interval(interval: integer ): integer Set the time interval between future blocks in the blockchain, in milliseconds. If the timestamp

Source: https://docs.chromia.com/pages/rell-stdlib/-rell-system-library/rell.test/set_block_interval/

FUNCTION

# set\_block\_interval

```signature
function set_block_interval(interval: integer): integer
```

Set the time interval between future blocks in the blockchain, in milliseconds.

If the timestamp for the next block has been explicitly set by calling
`rell.test.set_next_block_time()` or `rell.test.set\_next\_block\_time\_delta(),
the new interval does not take effect until after the next block.

**Parameters**

* **interval** — the time interval between blocks

**Returns**

the previous interval value, in milliseconds

**See Also**

1. [`rell.test.set_next_block_time()` - Rell Standard Library](https://docs.chromia.com/pages/rell-stdlib/-rell-system-library/rell.test/set_next_block_time/)
2. [`rell.test.set_next_block_time_delta()` - Rell Standard Library](https://docs.chromia.com/pages/rell-stdlib/-rell-system-library/rell.test/set_next_block_time_delta/)
3. [`rell.test.block` - Rell Standard Library](https://docs.chromia.com/pages/rell-stdlib/-rell-system-library/rell.test/block/)

Since 0.13.3

[View this page on docs.chromia.com](https://docs.chromia.com/pages/rell-stdlib/-rell%20-system%20-library/rell.test/set_block_interval.html)Generated API reference, mirrored from the live docs