Popover · base-ui-svelte

API Reference

Props mirror Base UI React where applicable, adapted for Svelte 5. Native HTML attributes for the rendered element are also accepted unless noted.

Popover.Root

Groups all parts of the popover. Doesn't render its own HTML element.

Props

open boolean —

Name: open
Description: Whether the component is open (controlled).
Type: boolean | undefined

defaultOpen boolean false

Name: defaultOpen
Description: Whether the component is initially open (uncontrolled).
Type: boolean
Default: false

onOpenChange function —

Name: onOpenChange
Description: Event handler called when the open state changes.
Type: ((open: boolean, eventDetails: { reason: OpenChangeReason }) => void) | undefined

onOpenChangeComplete function —

Name: onOpenChangeComplete
Description: Event handler called after any animations complete when the popover is opened or closed.
Type: ((open: boolean) => void) | undefined

openOnHover boolean —

Name: openOnHover
Description: —
Type: boolean

delay number 0

Name: delay
Description: Open delay when openOnHover is set (ms).
Type: number
Default: 0

closeDelay number 0

Name: closeDelay
Description: Close delay when leaving under hover (ms).
Type: number
Default: 0

modal PopoverModal false

Name: modal
Description: Whether the popover enters a modal state when open. - true: document scroll locked (except hover-open), outside interaction limited - false: no scroll lock - 'trap-focus': focus trap without scroll lock
Type: PopoverModal
Default: false

handle PopoverHandle —

Name: handle
Description: Imperative handle from .
Type: PopoverHandle | undefined

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet<[{ open: boolean; payload: unknown }]>

Data attributes

Attribute	Description
`data-closed`	Present when the part is closed.
`data-open`	Present when the part is open.

Popover.Arrow

Displays an element positioned against the popover anchor. Renders a <div> element.

Props

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Data attributes

Attribute	Description
`data-closed`	Present when the popup is closed.
`data-open`	Present when the popup is open.

Popover.Backdrop

An overlay displayed beneath the popover. Renders a <div> element.

Props

render string —

Name: render
Description: HTML element tag to render instead of the default host element.
Type: string

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Data attributes

Attribute	Description
`data-closed`	Present when the popup is closed.
`data-ending-style`	Present when the popup is animating out.
`data-open`	Present when the popup is open.
`data-starting-style`	Present when the popup begins animating in.

Popover.Close

A button that closes the popover. Renders a <button> element.

Props

render string —

Name: render
Description: HTML element tag to render instead of the default host element.
Type: string

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Popover.Description

A paragraph with additional information about the popover. Renders a <p> element.

Props

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Popover.Popup

A container for the popover contents. Renders a <div> element.

Props

render string —

Name: render
Description: HTML element tag to render instead of the default host element.
Type: string

initialFocus FocusTarget —

Name: initialFocus
Description: Determines the element to focus when the popover is opened. By default, focus moves to the first tabbable element inside the popup, except when the popover is opened by touch — then the popup itself is focused to avoid opening the virtual keyboard. false: Do not move focus.true: Move focus based on the default behavior (first tabbable element or popup).RefObject: Move focus to the ref element.function: Called with the interaction type (mouse, touch, pen, or keyboard). Return an element to focus, true to use the default behavior, null to fall back to the default behavior, or false/undefined to do nothing.
Type: FocusTarget

finalFocus FocusTarget —

Name: finalFocus
Description: Determines the element to focus when the popover is closed. false: Do not move focus.true: Move focus based on the default behavior (trigger or previously focused element).RefObject: Move focus to the ref element.function: Called with the interaction type (mouse, touch, pen, or keyboard). Return an element to focus, true to use the default behavior, null to fall back to the default behavior, or false/undefined to do nothing.
Type: FocusTarget

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Data attributes

Attribute	Description
`data-closed`	Present when the popup is closed.
`data-ending-style`	Present when the popup is animating out.
`data-open`	Present when the popup is open.
`data-starting-style`	Present when the popup begins animating in.

Popover.Portal

A portal element that moves the popup to a different part of the DOM. By default, the portal element is appended to <body>. Renders a <div> element.

Props

container HTMLElement | string | null —

Name: container
Description: A parent element to render the portal element into.
Type: HTMLElement | string | null

keepMounted boolean false

Name: keepMounted
Description: Whether to keep the portal mounted in the DOM while the popup is hidden.
Type: boolean
Default: false

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Popover.Positioner

Positions the popover against the trigger. Renders a <div> element.

Props

side ly o 'bottom'

Name: side
Description: Which side of the anchor element to align the popup against. May automatically change to avoid collisions.
Type: ly o
Default: 'bottom'

align n; s 'center'

Name: align
Description: How to align the popup relative to the specified side.
Type: n; s
Default: 'center'

sideOffset lean, 0

Name: sideOffset
Description: Distance between the anchor and the popup in pixels. Also accepts a function that returns the distance to read the dimensions of the anchor and positioner elements, along with its side and alignment. The function takes a data object parameter with the following properties: data.anchor: the dimensions of the anchor element with properties width and height.data.positioner: the dimensions of the positioner element with properties width and height.data.side: which side of the anchor element the positioner is aligned against.data.align: how the positioner is aligned relative to the specified side.
Type: lean,
Default: 0

alignOffset eReaso 0

Name: alignOffset
Description: Additional offset along the alignment axis in pixels. Also accepts a function that returns the offset to read the dimensions of the anchor and positioner elements, along with its side and alignment. The function takes a data object parameter with the following properties: data.anchor: the dimensions of the anchor element with properties width and height.data.positioner: the dimensions of the positioner element with properties width and height.data.side: which side of the anchor element the positioner is aligned against.data.align: how the positioner is aligned relative to the specified side.
Type: eReaso
Default: 0

collisionPadding erDelay(reason: OpenChang… 5

Name: collisionPadding
Description: Additional space to maintain from the edge of the collision boundary.
Type: erDelay(reason: OpenChangeReason): voi
Default: 5

collisionBoundary (reason: OpenCh 'clipping-ancestors'

Name: collisionBoundary
Description: An element or a rectangle that delimits the area that the popup is confined to.
Type: (reason: OpenCh
Default: 'clipping-ancestors'

collisionAvoidance elHover(): void; —

Name: collisionAvoidance
Description: Determines how to handle collisions when positioning the popup. side controls overflow on the preferred placement axis (top/bottom or left/right): 'flip': keep the requested side when it fits; otherwise try the opposite side
(top and bottom, or left and right).
'shift': never change side; keep the requested side and move the popup within the clipping boundary so it stays visible.
'none': do not correct side-axis overflow. align controls overflow on the alignment axis (start/center/end): 'flip': keep side, but swap start and end when the requested alignment overflows.
'shift': keep side and requested alignment, then nudge the popup along the alignment axis to fit.
'none': do not correct alignment-axis overflow. fallbackAxisSide controls fallback behavior on the perpendicular axis when the preferred axis cannot fit: 'start': allow perpendicular fallback and try the logical start side first
(top before bottom, or left before right in LTR).
'end': allow perpendicular fallback and try the logical end side first
(bottom before top, or right before left in LTR).
'none': do not fallback to the perpendicular axis. When side is 'shift', explicitly setting align only supports 'shift' or 'none'.
If align is omitted, it defaults to 'flip'.
Type: elHover(): void;

arrowPadding er: bo 5

Name: arrowPadding
Description: Minimum distance to maintain between the arrow and the edges of the popup. Use it to prevent the arrow element from hanging out of the rounded corners of a popup.
Type: er: bo
Default: 5

sticky only de false

Name: sticky
Description: Whether to maintain the popup in the viewport after the anchor element was scrolled out of view.
Type: only de
Default: false

positionMethod ly lastOpenChangeR 'absolute'

Name: positionMethod
Description: Maps to Floating UI strategy (absolute | fixed).
Type: ly lastOpenChangeR
Default: 'absolute'

strategy descriptionId: str —

Name: strategy
Description: —
Type: descriptionId: str

anchor eturnType<typeof createPr… —

Name: anchor
Description: Override the positioning anchor (element or virtual element).
Type: eturnType<typeof createPresence

disableAnchorTracking olean, false

Name: disableAnchorTracking
Description: When true, skip continuous layout tracking of the anchor (position once; no resize/scroll auto-updates beyond the initial compute).
Type: olean,
Default: false

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Data attributes

Attribute	Description
`data-closed`	Present when the popup is closed.
`data-open`	Present when the popup is open.

Popover.Title

A heading that labels the popover. Renders an <h2> element.

Props

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Popover.Trigger

A button that opens the popover. Renders a <button> element.

Props

render string —

Name: render
Description: HTML element tag to render instead of the default host element.
Type: string

disabled boolean false

Name: disabled
Description: Whether the control ignores user interaction.
Type: boolean
Default: false

id string —

Name: id
Description: ID of the trigger. In addition to being forwarded to the rendered element, it is also used to specify the active trigger for the popover in controlled mode (with the Popover.Root triggerId prop).
Type: string | undefined

handle PopoverHandle —

Name: handle
Description: Same handle as Root — enables triggers outside the Root tree.
Type: PopoverHandle | undefined

payload unknown —

Name: payload
Description: Optional payload associated when opening via this trigger.
Type: unknown

openOnHover boolean false

Name: openOnHover
Description: Whether the popover should also open when the trigger is hovered.
Type: boolean
Default: false

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Data attributes

Attribute	Description
`data-closed`	Present when the part is closed.
`data-disabled`	Present when the part is disabled.
`data-open`	Present when the part is open.

A viewport for displaying content transitions. This component is only required if one popup can be opened by multiple triggers, its content changes based on the trigger, and switching between them is animated. Renders a <div> element.

Props

render string —

Name: render
Description: HTML element tag to render instead of the default host element.
Type: string

children snippet —

Name: children
Description: Content rendered inside the part.
Type: Snippet

Data attributes

Attribute	Description
`data-closed`	Present when the part is closed.
`data-open`	Present when the part is open.