---
page_title: testencodebase64 function reference
description: The `testencodebase64` function converts a UTF-8 NFC string into a base64 blob to match the destination encoding. 
---

# `textencodebase64` Function

Encodes the input string to the destination encoding.
The output is base64-encoded to account for HCL's string encoding limitations: they must be UTF-8, NFC-normalised.

Packer uses the standard base64 alphabet as defined in
[RFC 4648 section 4](https://tools.ietf.org/html/rfc4648#section-4).

The `encoding_name` argument must contain one of the encoding names or aliases recorded in
[the IANA character encoding registry](https://www.iana.org/assignments/character-sets/character-sets.xhtml).

## Examples

```shell-session
# Usage: textencodebase64(input_string, encoding_name)
> textencodebase64("Hello World", "UTF-16LE")
SABlAGwAbABvACAAVwBvAHIAbABkAA==
```

## Related Functions

- [`base64encode`](/packer/docs/templates/hcl_templates/functions/encoding/base64encode) performs the opposite operation,
  encoding the UTF-8 bytes for a string as Base64.