# Sizes

:::info

Please read the [overview](/docs/theming/customization/overview) first to learn
how to properly customize the styling engine, and get type safety.

:::

## Example

Here's an example of how to customize sizes in Chakra UI.

```tsx title="theme.ts"
import { createSystem, defaultConfig, defineConfig } from "@chakra-ui/react"

const customConfig = defineConfig({
  theme: {
    tokens: {
      sizes: {
        "1/7": { value: "14.285%" },
        "2/7": { value: "28.571%" },
        "3/7": { value: "42.857%" },
      },
    },
  },
})

export const system = createSystem(defaultConfig, customConfig)
```

## Usage

Set the value of any size related properties, like `width`, `height`,
`minWidth`, `minHeight`, `maxWidth`, `maxHeight`, etc. to the `sizes` token.

```tsx
<Box width="1/7" height="2/7" />
```