> For the complete documentation index, see [llms.txt](https://docs.fact-finder.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fact-finder.com/integration/integrating-the-navigation-module/restricting-to-a-lower-navigation-level.md).

# Restricting to a lower navigation level

Deeper navigation, or navigation at a lower level, requires a combination of filters when you first call the FactFinder Navigation module.

### Filtering for a simple data field

When you submit a deeper navigation call, pass the full filter combination in the correct order. If you filter with data fields, you need to know which FactFinder field contains each level. Assume the categories are stored in `category0`, `category1`, and `category2`, where `category0` is the top navigation level.

For example, if navigation should go from the top-level category `Clothing` to the subcategory `Trousers` and then to `Jeans`, the REST call should look like this:

```language-plaintext
../rest/{apiversion}/navigation/{channel}?filter=category0:Clothing&filter=category1:Trousers&filter=category2:Jeans
```

### Filtering for a category path field

By following the schema below, you can generate all filters required for deeper navigation from the field names and the selected navigation path.

**Schema:** FILTER\_NAME:VALUE1/VALUE2/.../VALUEX.

Please note the suffix `ROOT` after the filter parameter.

In this example, the resulting filter has the name `categoryROOT/Clothing` and the value `Trousers`. Pass it in addition to the main category filter. For readability, the slashes in the example URLs are not URL-encoded.

```language-plaintext
../rest/{apiversion}/navigation/{channel}?filter=category:Clothing&filter=categoryROOT/Clothing:Trousers
```

```language-plaintext
../rest/{apiversion}/navigation/{channel}?filter=category:Clothing&filter=categoryROOT/Clothing:Trousers&filter=categoryROOT/Clothing/Trousers:Jeans
```


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