---
title: now() function
description: now() is a function option that, by default, returns the current system time.
url: https://docs.influxdata.com/flux/v0/stdlib/universe/now/
estimated_tokens: 766
product: Flux
version: v0
---

# now() function

-   Flux 0.7.0+
-   View InfluxDB support

`now()` is a function option that, by default, returns the current system time.

#### now() vs system.time()

`now()` returns the current system time (UTC). `now()` is cached at runtime, so all executions of `now()` in a Flux script return the same time value. `system.time()` returns the system time (UTC) at which `system.time()` is executed. Each instance of `system.time()` in a Flux script returns a unique value.

##### Function type signature

```js
() => time
```

For more information, see [Function type signatures](/flux/v0/function-type-signatures/).

## Examples

-   [Use the current UTC time as a query boundary](#use-the-current-utc-time-as-a-query-boundary)
-   [Define a custom now time](#define-a-custom-now-time)

### Use the current UTC time as a query boundary

```js
data
    |> range(start: -10h, stop: now())
```

### Define a custom now time

```js
option now = () => 2022-01-01T00:00:00Z
```

#### Related

-   [today() function](/flux/v0/stdlib/universe/today/)
-   [system.time() function](/flux/v0/stdlib/system/time/)

[date/time](/flux/v0/tags/date/time/)