Encode to base64: base64_encode

The base64_encode filter converts a string or bytes value into its base64-encoded representation. Base64 encoding transforms binary data into a text format that uses only printable ASCII characters, making it safe to include in places that only support text.

This is useful when you need to send binary data or credentials through text-only channels. For example, some REST APIs require authentication headers to be base64-encoded, certain MQTT payloads need binary data encoded as text, or you might need to embed image data in a notification. The filter accepts both strings and raw bytes, encoding them into a standard base64 string.

Usage

Here’s how to use this template function. Copy any example and adjust it to your setup.

{{ "Hello, World!" | base64_encode }}

SGVsbG8sIFdvcmxkIQ==

Function signature

The signature is a technical summary of this template function. It shows the name of the function, the values (called parameters) it accepts, and what type of data each parameter expects (for example, a piece of text or a number).

Function parameters that have a = with a value after them are optional. If you leave them out, the default value shown is used automatically. Function parameters without a default are required.

value | base64_encode() -> str

Function parameters

The following parameters can be provided to this filter.

Good to know

• Strings are encoded as UTF-8 before being base64-encoded.
• The result includes = padding characters when the input length is not a multiple of three.

Try it yourself

Ready to test this? Open Developer tools > Template, paste the example into the Template editor, and watch the result update on the right. Edit the values to see how the function adapts to your own entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more].

More examples

Real scenarios where this function comes up in automations and templates. Copy any example and adapt it to your setup.

Create a basic auth header

Build an HTTP Basic Authentication header by base64-encoding credentials.

{{ ("username:password") | base64_encode }}

dXNlcm5hbWU6cGFzc3dvcmQ=

Encode sensor data for transmission

Encode a sensor value for inclusion in a base64-only payload.

{{ states("sensor.temperature") | base64_encode }}

MjEuNQ==

Still stuck?

The Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with your template and expected result, or share on our subreddit /r/homeassistant.

Related template functions

These functions work well alongside this one:

• Decode from base64: base64_decode - Decodes a base64-encoded string.