> For the complete documentation index, see [llms.txt](https://indexone.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://indexone.gitbook.io/docs/product-guides/index-construction.md).

# Index Construction

**What is index construction?**

Index construction refers to the process of selecting and weighting a group of securities to create an index that represents a particular market or sector.

The process of index construction in finance is critical for investors, as it provides a benchmark against which to measure the performance of their investments.<br>

What is custom indexing?

Custom indexing in finance refers to the process of [creating an index that is tailored to a specific client's investment objectives or preferences. ](https://indexone.io/customindexing)

This approach allows investors to create an index that reflects their specific views on market trends or their investment strategy.<br>

Here are the articles in this section:

{% content-ref url="/pages/ZIq5BSMuVGpAiacPXgjB" %}
[Universe, Weighting and Specifications](/docs/product-guides/index-construction/universe-weighting-and-specifications.md)
{% endcontent-ref %}

{% content-ref url="/pages/wNSxwsutQPUCk6NBU9rF" %}
[Drag functionality](/docs/product-guides/index-construction/drag-functionality.md)
{% endcontent-ref %}

{% content-ref url="/pages/cxhTSnXrKEdPCPJ8obIH" %}
[Index Universe](/docs/product-guides/index-construction/index-universe.md)
{% endcontent-ref %}

{% content-ref url="/pages/gCbdeJQzkQlNGgLAcVMu" %}
[How to build a rules-based index](/docs/product-guides/index-construction/how-to-build-a-rules-based-index.md)
{% endcontent-ref %}

{% content-ref url="/pages/H3tLDNqwBZCW5etQ9sjy" %}
[How to use custom code to build an index](/docs/product-guides/index-construction/how-to-use-custom-code-to-build-an-index.md)
{% endcontent-ref %}


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