| CARVIEW |
Select Language
HTTP/2 200
x-guploader-uploadid: AAwnv3K9l1yYHxw37-h0f5CxFU1Hv9_isjYpHj5KAW7Ji_ENQqxb0pSPrKXrtBjaqc6l2tiU
x-goog-generation: 1760058382440198
x-goog-metageneration: 1
x-goog-stored-content-encoding: identity
x-goog-stored-content-length: 136564
x-goog-meta-goog-reserved-file-mtime: 1760056865
x-goog-hash: crc32c=aKDdoA==, md5=OkJCCkJRqhno6VnQ6PVLmQ==
x-goog-storage-class: STANDARD
accept-ranges: none
expires: Sun, 12 Oct 2025 10:12:42 GMT
cache-control: public, max-age=3600
last-modified: Fri, 10 Oct 2025 01:06:22 GMT
etag: W/"3a42420a4251aa19e8e959d0e8f54b99"
content-type: text/html
age: 0
alt-svc: h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
alt-svc: clear
referrer-policy: strict-origin-when-cross-origin
x-content-type-options: nosniff
strict-transport-security: max-age=63072000
content-security-policy: default-src 'self'; script-src 'report-sample' 'self' 'wasm-unsafe-eval' https://www.google-analytics.com/analytics.js https://www.googletagmanager.com/gtag/js assets.codepen.io production-assets.codepen.io https://js.stripe.com 'sha256-XNBp89FG76amD8BqrJzyflxOF9PaWPqPqvJfKZPCv7M=' 'sha256-YCNoU9DNiinACbd8n6UPyB/8vj0kXvhkOni9/06SuYw=' 'sha256-PZjP7OR6mBEtnvXIZfCZ5PuOlxoDF1LDZL8aj8c42rw='; script-src-elem 'report-sample' 'self' 'wasm-unsafe-eval' https://www.google-analytics.com/analytics.js https://www.googletagmanager.com/gtag/js assets.codepen.io production-assets.codepen.io https://js.stripe.com 'sha256-XNBp89FG76amD8BqrJzyflxOF9PaWPqPqvJfKZPCv7M=' 'sha256-YCNoU9DNiinACbd8n6UPyB/8vj0kXvhkOni9/06SuYw=' 'sha256-PZjP7OR6mBEtnvXIZfCZ5PuOlxoDF1LDZL8aj8c42rw='; style-src 'report-sample' 'self' 'unsafe-inline'; object-src 'none'; base-uri 'self'; connect-src 'self' developer.allizom.org bcd.developer.allizom.org bcd.developer.mozilla.org updates.developer.allizom.org updates.developer.mozilla.org https://*.google-analytics.com https://*.analytics.google.com https://*.googletagmanager.com https://incoming.telemetry.mozilla.org https://observatory-api.mdn.allizom.net https://observatory-api.mdn.mozilla.net https://api.github.com/search/issues stats.g.doubleclick.net https://api.stripe.com; font-src 'self'; frame-src 'self' interactive-examples.mdn.mozilla.net interactive-examples.mdn.allizom.net mdn.github.io live-samples.mdn.mozilla.net live-samples.mdn.allizom.net *.mdnplay.dev *.mdnyalp.dev *.play.test.mdn.allizom.net https://v2.scrimba.com https://scrimba.com jsfiddle.net www.youtube-nocookie.com codepen.io survey.alchemer.com https://js.stripe.com; img-src 'self' data: *.githubusercontent.com *.googleusercontent.com *.gravatar.com mozillausercontent.com firefoxusercontent.com profile.stage.mozaws.net profile.accounts.firefox.com developer.mozilla.org mdn.dev interactive-examples.mdn.mozilla.net interactive-examples.mdn.allizom.net wikipedia.org upload.wikimedia.org https://mdn.github.io/shared-assets/ https://mdn.dev/ https://*.google-analytics.com https://*.googletagmanager.com www.gstatic.com; manifest-src 'self'; media-src 'self' archive.org videos.cdn.mozilla.net https://mdn.github.io/shared-assets/; child-src 'self'; worker-src 'self';
x-frame-options: DENY
origin-trial: AxVILwizhbMjxFeHOn1P3R8niO1RJY/smaK4B4d1rLzc1gTaxtXMSaTi+FoigYgCw40uFRDwFcEAeqDR+vVLOW4AAABfeyJvcmlnaW4iOiJodHRwczovL2RldmVsb3Blci5tb3ppbGxhLm9yZyIsImZlYXR1cmUiOiJQcml2YXRlQXR0cmlidXRpb25WMiIsImV4cGlyeSI6MTc0MjA3OTYwMH0=
x-cloud-trace-context: 289e297500135992d6216e4428a1583c
date: Sun, 12 Oct 2025 09:12:42 GMT
server: Google Frontend
via: 1.1 google
vary: Accept-Encoding
content-encoding: gzip
x-cache: miss
WheelEvent: deltaY property - Web APIs | MDN
Toggle sidebar
WheelEvent: deltaY property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The WheelEvent.deltaY read-only property is a
double representing the vertical scroll amount in the
WheelEvent.deltaMode unit.
You must check the deltaMode property to determine the unit of the deltaY value. Do not assume that the deltaY value is specified in pixels. Some browsers, for compatibility reasons, may return different units for the deltaY value depending on whether deltaMode has been accessed, to accommodate for websites not explicitly checking the deltaMode property.
Value
A number.
Examples
js
const syntheticEvent = new WheelEvent("syntheticWheel", {
deltaY: 4,
deltaMode: 0,
});
console.log(syntheticEvent.deltaY);
Specifications
| Specification |
|---|
| UI Events # dom-wheelevent-deltay |
Browser compatibility
Loading…