> For the complete documentation index, see [llms.txt](https://calnix.gitbook.io/eth-dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://calnix.gitbook.io/eth-dev/gas-opt/compact-strings.md).

# Compact Strings

EVM stores data in 32 byte 'buckets' or 'slots'.

Strings are arrays of UTF-8 characters, and arrays are basically a fixed length sequence of storage slots located next to each other. Therefore, like everything else we need to think in terms of storage buckets

**This means that when we compile our contracts, we would prefer to use a single slot for the strings we use.**

Each character in a string is a UTF-8 Encoded byte, meaning that your strings can be up to 32 characters in length if you do not use specially encoded characters like emojis to be contained in a single storage slot.

{% hint style="info" %}
Here's a great resource to look up how many bytes a string takes up under UTF-8 Encoding. <https://mothereff.in/byte-counter>\
<https://blog.hubspot.com/website/what-is-utf-8>
{% endhint %}