fastapi/docs/en/docs/advanced/templates.md

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# Templates { #templates }
You can use any template engine you want with **FastAPI**.
A common choice is Jinja2, the same one used by Flask and other tools.
There are utilities to configure it easily that you can use directly in your **FastAPI** application (provided by Starlette).
## Install dependencies { #install-dependencies }
Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and install `jinja2`:
<div class="termy">
```console
$ pip install jinja2
---> 100%
```
</div>
## Using `Jinja2Templates` { #using-jinja2templates }
* Import `Jinja2Templates`.
* Create a `templates` object that you can reuse later.
* Declare a `Request` parameter in the *path operation* that will return a template.
* Use the `templates` you created to render and return a `TemplateResponse`, pass the name of the template, the request object, and a "context" dictionary with key-value pairs to be used inside of the Jinja2 template.
{* ../../docs_src/templates/tutorial001.py hl[4,11,15:18] *}
/// note
Before FastAPI 0.108.0, Starlette 0.29.0, the `name` was the first parameter.
Also, before that, in previous versions, the `request` object was passed as part of the key-value pairs in the context for Jinja2.
///
/// tip
By declaring `response_class=HTMLResponse` the docs UI will be able to know that the response will be HTML.
///
/// note | Technical Details
You could also use `from starlette.templating import Jinja2Templates`.
**FastAPI** provides the same `starlette.templating` as `fastapi.templating` just as a convenience for you, the developer. But most of the available responses come directly from Starlette. The same with `Request` and `StaticFiles`.
///
## Writing templates { #writing-templates }
Then you can write a template at `templates/item.html` with, for example:
```jinja hl_lines="7"
{!../../docs_src/templates/templates/item.html!}
```
### Template Context Values { #template-context-values }
In the HTML that contains:
{% raw %}
```jinja
Item ID: {{ id }}
```
{% endraw %}
...it will show the `id` taken from the "context" `dict` you passed:
```Python
{"id": id}
```
For example, with an ID of `42`, this would render:
```html
Item ID: 42
```
### Template `url_for` Arguments { #template-url-for-arguments }
You can also use `url_for()` inside of the template, it takes as arguments the same arguments that would be used by your *path operation function*.
So, the section with:
{% raw %}
```jinja
<a href="{{ url_for('read_item', id=id) }}">
```
{% endraw %}
...will generate a link to the same URL that would be handled by the *path operation function* `read_item(id=id)`.
For example, with an ID of `42`, this would render:
```html
<a href="/items/42">
```
## Templates and static files { #templates-and-static-files }
You can also use `url_for()` inside of the template, and use it, for example, with the `StaticFiles` you mounted with the `name="static"`.
```jinja hl_lines="4"
{!../../docs_src/templates/templates/item.html!}
```
In this example, it would link to a CSS file at `static/styles.css` with:
```CSS hl_lines="4"
{!../../docs_src/templates/static/styles.css!}
```
And because you are using `StaticFiles`, that CSS file would be served automatically by your **FastAPI** application at the URL `/static/styles.css`.
## More details { #more-details }
For more details, including how to test templates, check <a href="https://www.starlette.dev/templates/" class="external-link" target="_blank">Starlette's docs on templates</a>.