---
title: "convertFilter | JavaScript maps SDK"
description: "Documentation for MapTiler SDK"
---

> For AI agents: a documentation index is available at [/llms.txt](https://docs.maptiler.com/llms.txt). Markdown versions of all pages are available by appending .md to any URL.

# Function convertFilter

-   convertFilter(  
        filter: [FilterSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/FilterSpecification/),  
        expectedTypes?: [ExpectedTypes](https://docs.maptiler.com/sdk-js/api-reference/types/Externals.ExpectedTypes/),  
    ): [ExpressionFilterSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ExpressionFilterSpecification/)[](#convertfilter)
    
    #### Parameters
    
    -   filter: [FilterSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/FilterSpecification/)
    -   `Optional`expectedTypes: [ExpectedTypes](https://docs.maptiler.com/sdk-js/api-reference/types/Externals.ExpectedTypes/)
    
    #### Returns [ExpressionFilterSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ExpressionFilterSpecification/)