Human-readable duration: timedelta_string

The timedelta_string template function converts a timedelta object into a human-readable string like “2 hours” or “1 day 30 minutes”. Unlike time_since and time_until, which compute the duration from the current time to a given datetime, timedelta_string works directly on an already-computed timedelta. This makes it useful when you’ve already calculated a duration from a subtraction or from a sensor, and just want to display it nicely.

Negative timedeltas are formatted using their absolute value.

You can control the level of detail with the optional precision parameter, which determines how many time components (years, months, days, hours, minutes, seconds) to include.

Usage

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

{{ timedelta_string(trigger.to_state.last_changed - trigger.from_state.last_changed) }}

15 minutes

{{ (trigger.to_state.last_changed - trigger.from_state.last_changed) | timedelta_string }}

15 minutes

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.

timedelta_string(
    value: timedelta,
    precision: int = 1,
) -> str

Function parameters

The following parameters can be provided to this function.

Controlling precision

By default, timedelta_string returns only the largest time component. Increase the precision to include more detail.

{{ timedelta_string(timedelta(hours=2, minutes=30), 1) }}

3 hours

{{ timedelta_string(timedelta(hours=2, minutes=30), 2) }}

2 hours 30 minutes

{{ timedelta_string(timedelta(hours=1, minutes=54, seconds=33), 0) }}

1 hour 54 minutes 33 seconds

Good to know

• If the input is not a timedelta, it is returned unmodified.
• Negative timedeltas are formatted using their absolute value.
• Durations shorter than one second return "0 seconds".
• If you want to go the other direction — display how long ago a datetime was, or how long until a future one — use time_since or time_until instead.

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.

Show how long a door has been open

Display the elapsed time between two state changes in an automation.

{% set open_for = trigger.to_state.last_changed - trigger.from_state.last_changed %}
Open for {{ timedelta_string(open_for, 2) }}

Open for 15 minutes 30 seconds

Format a duration from a sensor

Some integrations expose durations as ISO 8601 strings. Parse and display them.

{% set duration = as_timedelta(states("sensor.runtime")) %}
Running for {{ timedelta_string(duration) }}

Running for 3 hours

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:

• Create a time duration: timedelta - Creates a timedelta object from numeric time components.

• Parse duration string: as_timedelta - Parses an ISO 8601 duration string into a timedelta object.

• Human-readable time elapsed: time_since - Returns a human-readable string describing how much time has passed since a datetime.

• Human-readable time remaining: time_until - Returns a human-readable string describing how much time remains until a datetime.

• Relative time (deprecated): relative_time - Returns a human-readable string describing how long ago a datetime was.