> For the complete documentation index, see [llms.txt](https://docs.fastn.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fastn.ai/flow-setup-essentials/designing-a-flow/loop.md).
# Loop
The **Loop** component repeats a set of actions multiple times within your flow. Use it when you need to iterate over a list of items (such as processing each record from an API response), run a block a fixed number of times, or keep executing while a condition remains true. Fastn supports three loop types: **Loop N times**, **Loop over data**, and **While loop**.
> You can select the Loop Type and the Data you want to loop over, mapping it from previous flow steps.
* **Loop N times**: Run a block a fixed number of times.
* **Loop over data**: Iterate through each item in a list.
* **While loop**: Keep looping as long as a condition is true.
Use **End Loop** to mark where the loop finishes.
In the example shown, the **Loop Type** is set to *Loop over data,* and the **Loop Data** field is mapped from a previous step:
```
{{steps.sendMessage.output.message.blocks}}
```
This means the loop will go through each `block` inside the `message` output from the `sendMessage` step, allowing you to process every block one by one.
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