MD5 hash: md5

The md5 template function calculates the MD5 hash of a string and returns the result as a hexadecimal string. MD5 produces a 128-bit (32-character hex) hash value from any input string.

This is useful when you need to generate a consistent, fixed-length identifier from a variable-length string. For example, you might hash an entity ID to create a unique filename, generate a cache key, or create a deterministic identifier for use with external services. Note that MD5 is not considered cryptographically secure for password hashing or security purposes. For stronger hashing, use sha256 or sha512.

Usage

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

{{ md5("Hello, World!") }}

65a8e27d8879283831b664bd8b7f0ad4

{{ "Hello, World!" | md5 }}

65a8e27d8879283831b664bd8b7f0ad4

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 = are usually required. A few optional parameters have no default value, so the signature shows them without a = as well. To check whether a parameter is required, look at the parameter list below the signature. Each parameter is marked as Required or Optional.

The most common optional parameter without a default value is default. The default parameter sets the value a function returns when the function can’t produce a result, for example, when float gets text that isn’t a number. If you leave out default, there is no fallback value, so most functions raise an error and the template fails. The parameter list of each function says what happens. If you set default, the function returns your value instead.

round(
    value: Any,
    precision: int = 0,
    method: str = "common",
    default: Any,
) -> float | int | Any

md5(
    value: str,
) -> str

Function parameters

The following parameters can be provided to this function.

Good to know

• MD5 is not secure for passwords or sensitive data. Use sha256 or sha512 for those.
• The input is encoded as UTF-8 before hashing, and the output is lowercase hexadecimal, always 32 characters long.

Try it yourself

Ready to test this? Open Settings > 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.

Generate a unique identifier

Create a short, consistent identifier from an entity ID.

{{ "light.living_room_ceiling" | md5 }}

a3c2f8b1d4e5f6a7b8c9d0e1f2a3b4c5

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:

• SHA1 hash: sha1 - Calculates the SHA1 hash of a string.

• SHA256 hash: sha256 - Calculates the SHA256 hash of a string.

• SHA512 hash: sha512 - Calculates the SHA512 hash of a string.