---
title: experimental.alignTime() function
description: experimental.alignTime() shifts time values in input tables to all start at a common start time.
url: https://docs.influxdata.com/flux/v0/stdlib/experimental/aligntime/
estimated_tokens: 1129
product: Flux
version: v0
publisher: InfluxData
canonical: https://docs.influxdata.com/flux/v0/stdlib/experimental/aligntime/
date: '2024-04-08T16:01:02-06:00'
lastmod: '2024-04-08T16:01:02-06:00'
---

* Flux 0.66.0+

InfluxDB support

> [!Important]
> `experimental.alignTime()` is [subject to change at any time](/flux/v0/stdlib/experimental/#experimental-packages-are-subject-to-change).

`experimental.alignTime()` shifts time values in input tables to all start at a common start time.

##### Function type signature

```js
(<-tables: stream[B], ?alignTo: A) => stream[C] where B: Record, C: Record
```

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

## Parameters

### alignTo

Time to align tables to. Default is `1970-01-01T00:00:00Z`.

### tables

Input data. Default is piped-forward data (`<-`).

## Examples

### Compare month-over-month values

1. Window data by calendar month creating two separate tables (one for January and one for February).
2. Align tables to `2021-01-01T00:00:00Z`.

Each output table represents data from a calendar month.
When visualized, data is still grouped by month, but timestamps are aligned
to a common start time and values can be compared by time.

```js
import "experimental"

data
    |> window(every: 1mo)
    |> experimental.alignTime(alignTo: 2021-01-01T00:00:00Z)
```

[](#view-example-input-and-output)

View example input and output

#### Input data

|     \*\_start      |      \*\_stop      |       \_time       |\_value|
|--------------------|--------------------|--------------------|-------|
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-01T00:00:00Z| 32.1  |
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-02T00:00:00Z| 32.9  |
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-03T00:00:00Z| 33.2  |
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-04T00:00:00Z|  34   |
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-02-01T00:00:00Z| 38.3  |
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-02-02T00:00:00Z| 38.4  |
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-02-03T00:00:00Z| 37.8  |
|2021-01-01T00:00:00Z|2021-03-01T00:00:00Z|2021-02-04T00:00:00Z| 37.5  |

#### Output data

|     \*\_start      |      \*\_stop      |       \_time       |\_value|
|--------------------|--------------------|--------------------|-------|
|2021-01-01T00:00:00Z|2021-02-01T00:00:00Z|2021-01-01T00:00:00Z| 32.1  |
|2021-01-01T00:00:00Z|2021-02-01T00:00:00Z|2021-01-02T00:00:00Z| 32.9  |
|2021-01-01T00:00:00Z|2021-02-01T00:00:00Z|2021-01-03T00:00:00Z| 33.2  |
|2021-01-01T00:00:00Z|2021-02-01T00:00:00Z|2021-01-04T00:00:00Z|  34   |

|     \*\_start      |      \*\_stop      |       \_time       |\_value|
|--------------------|--------------------|--------------------|-------|
|2021-02-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-01T00:00:00Z| 38.3  |
|2021-02-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-02T00:00:00Z| 38.4  |
|2021-02-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-03T00:00:00Z| 37.8  |
|2021-02-01T00:00:00Z|2021-03-01T00:00:00Z|2021-01-04T00:00:00Z| 37.5  |

[transformations](/flux/v0/tags/transformations/)[date/time](/flux/v0/tags/date/time/)
| *_start | *_stop | _time | _value |
| --- | --- | --- | --- |
| *_start | *_stop | _time | _value |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-01T00:00:00Z | 32.1 |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-02T00:00:00Z | 32.9 |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-03T00:00:00Z | 33.2 |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-04T00:00:00Z | 34 |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-02-01T00:00:00Z | 38.3 |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-02-02T00:00:00Z | 38.4 |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-02-03T00:00:00Z | 37.8 |
| 2021-01-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-02-04T00:00:00Z | 37.5 |

| *_start | *_stop | _time | _value |
| --- | --- | --- | --- |
| *_start | *_stop | _time | _value |
| 2021-01-01T00:00:00Z | 2021-02-01T00:00:00Z | 2021-01-01T00:00:00Z | 32.1 |
| 2021-01-01T00:00:00Z | 2021-02-01T00:00:00Z | 2021-01-02T00:00:00Z | 32.9 |
| 2021-01-01T00:00:00Z | 2021-02-01T00:00:00Z | 2021-01-03T00:00:00Z | 33.2 |
| 2021-01-01T00:00:00Z | 2021-02-01T00:00:00Z | 2021-01-04T00:00:00Z | 34 |

| *_start | *_stop | _time | _value |
| --- | --- | --- | --- |
| *_start | *_stop | _time | _value |
| 2021-02-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-01T00:00:00Z | 38.3 |
| 2021-02-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-02T00:00:00Z | 38.4 |
| 2021-02-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-03T00:00:00Z | 37.8 |
| 2021-02-01T00:00:00Z | 2021-03-01T00:00:00Z | 2021-01-04T00:00:00Z | 37.5 |