# hover

> Whether the primary pointing device can hover over elements, from the hover media query: hover or none. Reported, not in either id.

Source: https://whiskerjs.com/signals/hover/ (last updated 2026-10-27)

**hover at a glance (from the library code, signalsVersion 14)**

| Field | Value |
| --- | --- |
| Component name | `hover` |
| In the visitorId | no (reported, kept out of both ids) |
| structuredId group | none |
| Hashing | plain value; a digest only when longer than 128 characters or not printable ASCII |
| Excluded under | no browser class |
| Inner timeout | 1000 ms |
| Added in | [signalsVersion 11](https://whiskerjs.com/whats-new/) |
| Collector revision | [1](https://whiskerjs.com/docs/api/#component) (reported as `revision` with every result) |

> **In plain words:**
>
> A mouse can rest over a link without clicking; a finger cannot. Browsers tell pages whether the main pointing device can hover. WhiskerJS records `hover` or `none`.

## What it reads

The CSS `hover` media feature through `window.matchMedia()`. Nothing else: no events, no pointer positions, no input is read.

## How the technique works

| Order | Query | Value reported |
| --- | --- | --- |
| 1 | `(hover: hover)` | `hover` |
| 2 | `(hover: none)` | `none` |

The first match is reported; no match gives `unavailable` with `no_match`.

## Why it helps

Together with `pointer` it separates mouse-driven devices from touch-first ones, and it is a cheap consistency check against the user agent and `touch_support` on your server.

## Stability

Stable on most devices; it changes with the primary input, like `pointer`. That is why it is reported but kept out of both ids for now; it can join the id once measurement shows it is stable. Added in library PR #29 (2026-10-27) at signalsVersion 11: it is outside both ids, so adding it changed no id and needed no version bump.

## Browser support and what blocks it

Every current engine answers the query. In the hosted CI runs of PR #29 (headless Chromium 153, Chrome 155, Firefox with and without its privacy settings, and WebKit, on a Linux server) every browser reported the same value in every collection. No browser class excludes it.

## Privacy

It says what kind of input device is in use, which the page could also learn from the user’s own clicks and taps. It needs no permission and shows no prompt. Leave it out with `collect({ exclude: ['hover'] })` if you do not need it; no id changes.

## How WhiskerJS handles noise and failures

| Status | ruleId | When |
| --- | --- | --- |
| `ok` |   | one of the values above |
| `unavailable` | `no_api` | no `matchMedia` |
| `unavailable` | `no_match` | no value matched |
| `blocked` | `threw`, `security_error` | `matchMedia` throws |
| `excluded` | `caller_excluded` | you excluded it |
| `timed_out` | `timeout`, `aborted` | budget or abort |

Like every component it also carries `durationMs` (how long its collector ran, 0.1 ms) and `revision` (1).

## Example value

```json
"hover": { "status": "ok", "value": "hover", "hashed": false, "durationMs": 0.1, "revision": 1 }
```

## Questions and answers

### Why does a phone report none?

A finger cannot hover: it either touches the screen or not. Phones and most tablets therefore report none, desktops with a mouse report hover.

### Does WhiskerJS track where the mouse hovers?

No. It asks the browser one yes-or-no question about the device's capability. No pointer events or positions are read.

## Related pages

- [any_hover](https://whiskerjs.com/signals/any-hover/): Hover for any input device.
- [pointer](https://whiskerjs.com/signals/pointer/): The accuracy of the primary pointer.
- [Component fields](https://whiskerjs.com/docs/api/#component): Status, value, durationMs and revision.