--- title: Stack description: >- The stack component organizes elements horizontally or vertically along the block or inline axis. api_version: 2026-01 api_name: checkout-ui-extensions source_url: html: >- https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/web-components/layout-and-structure/stack md: >- https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/web-components/layout-and-structure/stack.md --- # Stack The stack component organizes elements horizontally or vertically along the block or inline axis. Use stack to structure layouts, group related components, control spacing between elements, or create flexible arrangements that adapt to content. Stacks support gap spacing, alignment, wrapping, and distribution properties to create consistent, responsive layouts without custom CSS. For complex multi-column layouts with precise grid positioning, use [grid](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/web-components/layout-and-structure/grid). Stack supports one-dimensional layouts only — for content that needs both rows and columns, use [grid](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/web-components/layout-and-structure/grid). ### Support Targets (29) ### Supported targets * [purchase.​checkout.​actions.​render-before](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/navigation#navigation-target) * [purchase.​checkout.​block.​render](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/block#block-target) * [purchase.​checkout.​cart-line-item.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/order-summary#line-item-targets) * [purchase.​checkout.​cart-line-list.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/order-summary#checkout-cart-line-list-) * [purchase.​checkout.​contact.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/information#information-target) * [purchase.​checkout.​delivery-address.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/shipping#render-after-delivery-address-) * [purchase.​checkout.​delivery-address.​render-before](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/shipping#delivery-address-targets) * [purchase.​checkout.​footer.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/footer#footer-target) * [purchase.​checkout.​header.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/header#header-target) * [purchase.​checkout.​payment-method-list.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/payment#render-after-payment-methods-) * [purchase.​checkout.​payment-method-list.​render-before](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/payment#payment-targets) * [purchase.​checkout.​pickup-location-list.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/local-pickup#render-after-pickup-locations-) * [purchase.​checkout.​pickup-location-list.​render-before](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/local-pickup#location-list-targets) * [purchase.​checkout.​pickup-location-option-item.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/local-pickup#location-option-item-target) * [purchase.​checkout.​pickup-point-list.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/pickup-points#render-after-pickup-points-) * [purchase.​checkout.​pickup-point-list.​render-before](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/pickup-points#pickup-points-targets) * [purchase.​checkout.​reductions.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/order-summary#checkout-reductions-after-) * [purchase.​checkout.​reductions.​render-before](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/order-summary#reductions-targets) * [purchase.​checkout.​shipping-option-item.​details.​render](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/shipping#shipping-option-item-targets) * [purchase.​checkout.​shipping-option-item.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/shipping#render-after-shipping-option-) * [purchase.​checkout.​shipping-option-list.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/shipping#render-after-shipping-options-) * [purchase.​checkout.​shipping-option-list.​render-before](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/checkout/shipping#shipping-option-list-targets) * [purchase.​thank-you.​announcement.​render](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/thank-you/announcement#thank-you-announcement-) * [purchase.​thank-you.​block.​render](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/thank-you/block#block-target) * [purchase.​thank-you.​cart-line-item.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/thank-you/order-summary#line-item-targets) * [purchase.​thank-you.​cart-line-list.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/thank-you/order-summary#thank-you-cart-line-list-) * [purchase.​thank-you.​customer-information.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/thank-you/information#information-target) * [purchase.​thank-you.​footer.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/thank-you/footer#footer-target) * [purchase.​thank-you.​header.​render-after](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/targets/thank-you/header#header-target) #### Use cases * **Linear layouts**: Arrange elements in a horizontal row or vertical column with consistent spacing * **Alignment and distribution**: Control cross-axis alignment and main-axis justification to position children precisely *** ## Properties Configure the following properties on the stack component. * **accessibilityLabel** **string** A label that describes the purpose or contents of the element. When set, it will be announced to users using assistive technologies and will provide them with more context. Only use this when the element's content is not enough context for users using assistive technologies. * **accessibilityRole** **'aside' | 'footer' | 'header' | 'main' | 'section' | 'status' | 'none' | 'navigation' | 'ordered-list' | 'list-item' | 'list-item-separator' | 'unordered-list' | 'separator' | 'alert' | 'generic'** **Default: 'generic'** The semantic meaning of the stack's content, used by assistive technologies. * `aside`: Supporting content related to the main content. * `footer`: Information such as copyright, navigation links, and privacy statements. * `header`: A page or section header. * `main`: The primary content of the page. * `section`: A generic section that should have a heading or `accessibilityLabel`. * `status`: A live region with advisory information that is not urgent. * `none`: Strips semantic meaning while keeping visual styling. * `navigation`: A major group of navigation links. * `ordered-list`: A list of ordered items. * `list-item`: An item inside a list. * `list-item-separator`: A divider between list items. * `unordered-list`: A list of unordered items. * `separator`: A divider that separates sections of content. * `alert`: Important, usually time-sensitive information. * `generic`: A nameless container with no semantic meaning (renders a `
`). * **alignContent** **MaybeResponsive\>** **Default: 'normal'** Controls how lines of content are distributed along the cross axis when there is extra space. * `normal`: Default browser behavior. * `space-between`: Distributes lines evenly with no space at the edges. * `space-around`: Distributes lines evenly with equal space around each. * `space-evenly`: Distributes lines with equal space between and at the edges. * `stretch`: Stretches lines to fill the available space. * `center`: Packs lines toward the center. * `start`: Packs lines toward the start of the cross axis. * `end`: Packs lines toward the end of the cross axis. * **alignItems** **MaybeResponsive\>** **Default: 'normal'** Controls how child elements are aligned along the cross axis. * `normal`: Default browser behavior. * `stretch`: Stretches children to fill the cross axis. * `center`: Centers children along the cross axis. * `start`: Aligns children to the start of the cross axis. * `end`: Aligns children to the end of the cross axis. * **background** **'base' | 'subdued' | 'transparent'** **Default: 'transparent'** The background color of the stack. * `base`: The standard background color for general content areas. * `subdued`: A muted background for secondary or supporting content. * `transparent`: No background color (the default). * **blockSize** **MaybeResponsive\** **Default: 'auto'** The block size of the element (height in horizontal writing modes). Learn more about the [block-size property](https://developer.mozilla.org/en-US/docs/Web/CSS/block-size). * `SizeUnits`: Specific size values in pixels, percentages, or zero for precise control. * `auto`: Automatically sizes based on content and layout constraints. * **border** **BorderShorthand** **Default: 'none'** A shorthand for setting the border width, color, and style in a single property. Individual border properties (`borderWidth`, `borderStyle`) can override values set here. * **borderRadius** **MaybeAllValuesShorthandProperty\>** **Default: 'none'** The roundedness of the stack's corners. * `none`: Sharp corners with no rounding. * `small-100` / `small`: Subtle rounding for compact elements. * `base`: Standard rounding for most use cases. * `large` / `large-100`: More pronounced rounding for prominent containers. * `max`: Maximum rounding, creating a pill or circular shape. Supports 1-to-4-value shorthand syntax for specifying different radii per corner. * **borderStyle** **MaybeAllValuesShorthandProperty\ | ""** **Default: '' - meaning no override** Controls the visual style of the border on all sides, such as solid, dashed, or dotted. When set, this overrides the style value specified in the `border` property. Supports [1-to-4-value syntax](https://developer.mozilla.org/en-US/docs/Web/CSS/Shorthand_properties#edges_of_a_box) for specifying different styles per side: * One value: applies to all sides * Two values: applies to block sides (top/bottom) and inline sides (left/right) respectively * Three values: applies to block-start (top), inline sides (left/right), and block-end (bottom) respectively * Four values: applies to block-start (top), inline-end (right), block-end (bottom), and inline-start (left) respectively * **borderWidth** **MaybeAllValuesShorthandProperty\ | ''** **Default: '' - meaning no override** The thickness of the border on all sides. Supports 1-to-4-value shorthand syntax for specifying different widths per side. Overrides the width value set by `border`. * **columnGap** **MaybeResponsive\** **Default: '' - meaning no override** Adjust spacing between elements in the inline axis. This overrides the column value of `gap`. * **direction** **MaybeResponsive<"block" | "inline">** **Default: 'block'** Sets how the children are placed within the Stack. This uses [logical properties](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_logical_properties_and_values). * **display** **MaybeResponsive<"auto" | "none">** **Default: 'auto'** Sets the outer display type of the component. The outer type sets a component’s participation in [flow layout](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_flow_layout). * `auto`: the component’s initial value. The actual value depends on the component and context. * `none`: hides the component from display and removes it from the accessibility tree, making it invisible to screen readers. Learn more about the [display property](https://developer.mozilla.org/en-US/docs/Web/CSS/display). * **gap** **MaybeResponsive\>** **Default: 'none'** Adjust spacing between elements. A single value applies to both axes. A pair of values (eg `large-100 large-500`) can be used to set the inline and block axes respectively. * **id** **string** A unique identifier for the element. Use this to reference the element in JavaScript, link labels to form controls, or target specific elements for styling or scripting. * **inlineSize** **MaybeResponsive\** **Default: 'auto'** The inline size of the element (width in horizontal writing modes). Learn more about the [inline-size property](https://developer.mozilla.org/en-US/docs/Web/CSS/inline-size). * `SizeUnits`: Specific size values in pixels, percentages, or zero for precise control. * `auto`: Automatically sizes based on content and layout constraints. * **justifyContent** **MaybeResponsive\>** **Default: 'normal'** Controls how child elements are distributed along the main axis. * `normal`: Default browser behavior. * `space-between`: Distributes children evenly with no space at the edges. * `space-around`: Distributes children evenly with equal space around each. * `space-evenly`: Distributes children with equal space between and at the edges. * `stretch`: Stretches children to fill the available space. * `center`: Packs children toward the center. * `start`: Packs children toward the start of the main axis. * `end`: Packs children toward the end of the main axis. * **maxBlockSize** **MaybeResponsive\** **Default: 'none'** The maximum block size of the element (maximum height in horizontal writing modes). Learn more about the [max-block-size property](https://developer.mozilla.org/en-US/docs/Web/CSS/max-block-size). * **maxInlineSize** **MaybeResponsive\** **Default: 'none'** The maximum inline size of the element (maximum width in horizontal writing modes). Learn more about the [max-inline-size property](https://developer.mozilla.org/en-US/docs/Web/CSS/max-inline-size). * **minBlockSize** **MaybeResponsive\** **Default: '0'** The minimum block size of the element (minimum height in horizontal writing modes). Learn more about the [min-block-size property](https://developer.mozilla.org/en-US/docs/Web/CSS/min-block-size). * **minInlineSize** **MaybeResponsive\** **Default: '0'** The minimum inline size of the element (minimum width in horizontal writing modes). Learn more about the [min-inline-size property](https://developer.mozilla.org/en-US/docs/Web/CSS/min-inline-size). * **overflow** **'hidden' | 'visible'** **Default: 'visible'** Sets the overflow behavior of the element. * `visible`: The content that extends beyond the element’s container is visible. * `hidden`: Clips the content when it is larger than the element’s container. The element will not be scrollable and users will not be able to access the clipped content by dragging or using a scroll wheel on a mouse. * **padding** **MaybeResponsive\>** **Default: 'none'** The padding applied to all edges of the component. Supports [1-to-4-value syntax](https://developer.mozilla.org/en-US/docs/Web/CSS/Shorthand_properties#edges_of_a_box) using flow-relative values: * 1 value applies to all sides * 2 values apply to block (top/bottom) and inline (left/right) * 3 values apply to block-start (top), inline (left/right), and block-end (bottom) * 4 values apply to block-start (top), inline-end (right), block-end (bottom), and inline-start (left) **Examples:** `base`, `large none`, `base large-100 base small` Use `auto` to inherit padding from the nearest container with removed padding. * **paddingBlock** **MaybeResponsive\ | "">** **Default: '' - meaning no override** The block-direction padding (top and bottom in horizontal writing modes). Accepts a single value for both sides or two space-separated values for block-start and block-end. **Example:** `large none` applies `large` to the top and `none` to the bottom. Overrides the block value from `padding`. * **paddingBlockEnd** **MaybeResponsive\** **Default: '' - meaning no override** The block-end padding (bottom in horizontal writing modes). Overrides the block-end value from `paddingBlock`. * **paddingBlockStart** **MaybeResponsive\** **Default: '' - meaning no override** The block-start padding (top in horizontal writing modes). Overrides the block-start value from `paddingBlock`. * **paddingInline** **MaybeResponsive\ | "">** **Default: '' - meaning no override** The inline-direction padding (left and right in horizontal writing modes). Accepts a single value for both sides or two space-separated values for inline-start and inline-end. **Example:** `large none` applies `large` to the left and `none` to the right. Overrides the inline value from `padding`. * **paddingInlineEnd** **MaybeResponsive\** **Default: '' - meaning no override** The inline-end padding (right in LTR writing modes, left in RTL). Overrides the inline-end value from `paddingInline`. * **paddingInlineStart** **MaybeResponsive\** **Default: '' - meaning no override** The inline-start padding (left in LTR writing modes, right in RTL). Overrides the inline-start value from `paddingInline`. * **rowGap** **MaybeResponsive\** **Default: '' - meaning no override** Adjust spacing between elements in the block axis. This overrides the row value of `gap`. ### MaybeResponsive Makes a property responsive by allowing it to be set conditionally based on container query conditions. The value can be either a base value or a container query string. - \`T\`: Base value that applies in all conditions. - \`@container${string}\`: Container query string for conditional responsive styling based on container size. ```ts T | `@container${string}` ``` ### SizeUnitsOrAuto Represents size values that can also be set to \`auto\` for automatic sizing. - \`SizeUnits\`: Specific size values in pixels, percentages, or zero for precise control. - \`auto\`: Automatically sizes based on content and layout constraints. Learn more about the \[auto value]\(https://developer.mozilla.org/en-US/docs/Web/CSS/width#auto). ```ts SizeUnits | "auto" ``` ### SizeUnits Represents size values in pixels, percentages, or zero. - \`\` \`${number}px\` \`\`: Absolute size in pixels for fixed dimensions (such as \`100px\`, \`24px\`). - \`\` \`${number}%\` \`\`: Relative size as a percentage of the parent container (such as \`50%\`, \`100%\`). - \`0\`: Zero size, equivalent to no dimension. ```ts `${number}px` | `${number}%` | `0` ``` ### BorderShorthand A shorthand string for specifying border properties. Accepts a size alone (\`'base'\`), size with color (\`'base base'\`), or size with color and style (\`'base base dashed'\`). Omitted values use their defaults. ```ts ReducedBorderSizeKeyword | `${ReducedBorderSizeKeyword} ${ReducedColorKeyword}` | `${ReducedBorderSizeKeyword} ${ReducedColorKeyword} ${BorderStyleKeyword}` ``` ### ReducedBorderSizeKeyword The subset of border size values available for this component. - \`base\`: Standard border width. - \`large\`: Thick border for strong emphasis. - \`large-100\`: Extra thick border for maximum prominence. - \`large-200\`: The thickest available border. - \`none\`: No border. ```ts 'large' | 'base' | 'large-100' | 'large-200' | 'none' ``` ### ReducedColorKeyword The subset of border color values available for this component. - \`base\`: The standard border color for most contexts. ```ts 'base' ``` ### BorderStyleKeyword The visual style of a border. Learn more about \[border-style]\(https://developer.mozilla.org/en-US/docs/Web/CSS/border-style). - \`none\`: No border is rendered. - \`solid\`: A single continuous line. - \`dashed\`: A series of short dashes. - \`dotted\`: A series of round dots. - \`auto\`: The border style is determined automatically based on the surface's design system. ```ts "none" | "solid" | "dashed" | "dotted" | "auto" ``` ### MaybeAllValuesShorthandProperty Represents CSS shorthand properties that accept one to four values, following the \[CSS shorthand syntax]\(https://developer.mozilla.org/en-US/docs/Web/CSS/Shorthand\_properties#edges\_of\_a\_box). Supports specifying values for all four sides: top, right, bottom, and left. - \`T\`: Single value that applies to all four sides. - \`${T} ${T}\`: Two values for block axis (top/bottom) and inline axis (left/right). - \`${T} ${T} ${T}\`: Three values for block-start (top), inline axis (left/right), and block-end (bottom). - \`${T} ${T} ${T} ${T}\`: Four values for block-start (top), inline-end (right), block-end (bottom), and inline-start (left). ```ts T | `${T} ${T}` | `${T} ${T} ${T}` | `${T} ${T} ${T} ${T}` ``` ### SpacingKeyword ```ts SizeKeyword | "none" ``` ### SizeKeyword The design system's size scale, used to control the dimensions of components like avatars, icons, and thumbnails. Values range from \`"small-500"\` (smallest) through \`"base"\` (standard) to \`"large-500"\` (largest). Not all components support every size — check the component's \`size\` property type for its available options. ```ts "small-500" | "small-400" | "small-300" | "small-200" | "small-100" | "small" | "base" | "large" | "large-100" | "large-200" | "large-300" | "large-400" | "large-500" ``` ### MaybeTwoValuesShorthandProperty Represents CSS shorthand properties that accept one or two values. Supports specifying the same value for both dimensions or different values. - \`T\`: Single value that applies to both dimensions. - \`${T} ${T}\`: Two values for block axis (vertical) and inline axis (horizontal). ```ts T | `${T} ${T}` ``` ### SizeUnitsOrNone Represents size values that can also be set to \`none\` to remove the size constraint. - \`SizeUnits\`: Specific size values in pixels, percentages, or zero for precise control. - \`none\`: No size constraint, allowing unlimited growth. Learn more about the \[none value]\(https://developer.mozilla.org/en-US/docs/Web/CSS/max-width#none). ```ts SizeUnits | "none" ``` ### PaddingKeyword Defines the padding size for elements, using the standard size scale or \`none\` for no padding. - \`SizeKeyword\`: Standard padding sizes from the size scale for consistent spacing. - \`none\`: No padding. ```ts SizeKeyword | "none" ``` *** ## Examples ### Arrange items in a row with consistent spacing Lay out children in a horizontal sequence with consistent spacing. This example arranges four items in a row using `direction="inline"` and `gap="base"`. ## Arrange items in a row with consistent spacing ![A rendered example of the stack component](https://shopify.dev/assets/assets/images/templated-apis-screenshots/checkout-ui-extensions/2025-10/stack-default-CO-lvcid.png) ## html ```html Item 1 Item 2 Item 3 Item 4 ``` ### Space items apart with block direction Push the first and last items to opposite ends of a vertical stack. This example separates two text elements with `justifyContent="space-between"` and `direction="block"` so they pin to the top and bottom. ## html ```html Shipping Free ``` ### Align inline items with center alignment Align inline items along the cross axis. This example centers three status badges vertically with `alignItems="center"` on `direction="inline"`. ## html ```html Standard Processing Action needed ``` *** ## Best practices * **Use smaller gaps for related items**: Apply smaller gaps between tightly related elements like label-value pairs, and larger gaps between distinct groups. * **Keep spacing consistent**: Use the same gap value across stacks on the same page for visual harmony. * **Choose stack over grid for linear layouts**: Stack handles one-dimensional layouts (a single row or column) more simply than grid. Use [grid](https://shopify.dev/docs/api/checkout-ui-extensions/2026-01/web-components/layout-and-structure/grid) only when you need rows and columns. * **Set explicit direction**: Always specify `direction="inline"` or `direction="block"` so the layout intent is clear to other developers. ***