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# Read Heroes with Limit and Offset with FastAPI
When a client sends a request to get all the heroes, we have been returning them all.
But if we had **thousands** of heroes that could consume a lot of **computational resources**, network bandwidth, etc.
So, we probably want to limit it.
Let's use the same **offset** and **limit** we learned about in the previous tutorial chapters for the API.
/// info
In many cases, this is also called **pagination**.
///
## Add a Limit and Offset to the Query Parameters
Let's add `limit` and `offset` to the query parameters.
By default, we will return the first results from the database, so `offset` will have a default value of `0`.
And by default, we will return a maximum of `100` heroes, so `limit` will have a default value of `100`.
{* ./docs_src/tutorial/fastapi/limit_and_offset/tutorial001_py310.py ln[1:2,52:56] hl[1,53,55] *}
We want to allow clients to set different `offset` and `limit` values.
But we don't want them to be able to set a `limit` of something like `9999`, that's over `9000`! 😱
So, to prevent it, we add additional validation to the `limit` query parameter, declaring that it has to be **l**ess than or **e**qual to `100` with `le=100`.
This way, a client can decide to take fewer heroes if they want, but not more.
/// info
If you need to refresh how query parameters and their validation work, check out the docs in FastAPI:
* <a href="https://fastapi.tiangolo.com/tutorial/query-params/" class="external-link" target="_blank">Query Parameters</a>
* <a href="https://fastapi.tiangolo.com/tutorial/query-params-str-validations/" class="external-link" target="_blank">Query Parameters and String Validations</a>
* <a href="https://fastapi.tiangolo.com/tutorial/path-params-numeric-validations/" class="external-link" target="_blank">Path Parameters and Numeric Validations</a>
///
## Check the Docs UI
Now we can see that the docs UI shows the new parameters to control **limit** and **offset** of our data.
<img class="shadow" alt="Interactive API docs UI" src="/img/tutorial/fastapi/limit-and-offset/image01.png">
## Recap
You can use **FastAPI**'s automatic data validation to get the parameters for `limit` and `offset`, and then use them with the **session** to control ranges of data to be sent in responses.
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