---
page_title: timeadd function reference - Functions - Configuration Language
description: |-
  The timeadd function adds a duration to a timestamp, returning a new
  timestamp.
---

# `timeadd` function reference

This topic provices reference information about the `timeadd` function. 
`timeadd` adds a duration to a timestamp, returning a new timestamp.

## Introduction

The Terraform language represents timestamps as strings using [RFC
3339][rfc3339]'s Date and Time format.
`timeadd` requires that the `timestamp` argument is a string conforming to the Date and Time syntax.

## Syntax

Use the `timeadd` function with the following syntax:


```hcl
timeadd(timestamp, duration)
```

- `timestamp` is a string representation of a date in RFC 3339 format. Refer to the
  external RFC 3339's [Internet Date/Time Format section][date-time-format] for how to construct a timestamp string.
- `duration` is a string representation of a time difference. This string consists of
sequences of number and unit pairs, such as `"1.5h"` or `"1h30m"`. You may use
the following units:

  - `ns`: nanosecond
  - `us` or `µs`: microsecond
  - `ms`: millisecond
  - `s`: second
  - `m`: minute
  - `h`: hour

  To indicate a negative duration, make the first number negative, such as `"-2h5m"`.

The `timeadd` result is a string, also in RFC 3339 format, representing the result
of adding the given duration to the given timestamp.

## Example use case

This example adds ten minutes.

```hcl
> timeadd("2024-08-16T12:45:05Z", "10m")
"2024-08-16T12:55:05Z"
```

This example subtracts ten minutes by using a negative duration.

```hcl
> timeadd("2024-08-16T12:45:05Z", "-10m")
"2024-08-16T12:35:05Z"
```

# Related Functions

* [`timecmp`](/terraform/language/functions/timecmp) determines an ordering for two timestamps.

[rfc3339]: https://tools.ietf.org/html/rfc3339
[date-time-format]: https://datatracker.ietf.org/doc/html/rfc3339#section-5.6