Safari is the best way to see the sites on iPhone, iPad, and Mac. Safari Technology Preview gives you an early look at upcoming web technologies in macOS and iOS. Get the latest layout technologies, visual effects, developer tools, and more, so you can provide input on how they are implemented and deliver a best-in-class user experience on all Apple devices.

Preview the latest web technologies:
Get a preview of the latest advances in Safari web technologies, including HTML, JavaScript, and CSS. Safari Technology Preview includes the most recent version of WebKit, the rendering engine that powers Safari.

Easy to update:
You can update Safari Technology Preview right from the Mac App Store. Updates occur every few weeks and include the most WebKit.

Access powerful developer tools:
Use the latest version of the powerful Web Inspector and Responsive Design Mode to modify, debug, and optimize your websites.

Provide feedback:
Use Bug Reporter to send feedback directly to Apple about issues and enhancement requests. Simply select Report an Issue from the Help menu in Safari Technology Preview.

Run side-by-side with Safari:
Safari Technology Preview is a standalone app that works side-by-side with the current version of Safari, so you can continue to use and reference the current release.

Surf seamlessly with iCloud:
Safari Technology Preview works with iCloud, so you can access your latest Safari Favorites, bookmarks, and Reading List.

Keep current:
The WebKit blog keeps you up-to-date on the latest developments in HTML, JavaScript, and CSS.

New in this version:
Web Inspector
• Added autocomplete for experimental CSS Color values: hwb, lch, lab, color-mix, color-contrast (r275310)
• Changed grid overlay track size labels to show implicit auto value and no computed size (r275559)
• Fixed grid layout labels that were getting drawn outside the viewport (r275128)
• Fixed CSS Grid overlay track sizes when inline styles are applied to the element (r275293)
• Fixed a bug with more than two timeline recordings not showing a timescale (r275337)
• Fixed grid overlay areas appearing offset from their actual areas when the grid container has a border set (r275529)
• Fixed grid overlay to honor writing modes and RTL layout direction. (r275519)
• Fixed grid overlay line numbers showing implicit tracks with negative line numbers (r275558)
• Improved grid overlay label appearance (r275560)
• Removed the duplicate Box Model section from Layout panel in Elements Tab (r275545)

CSS
• Accounted for cover and contain when interpolating background-size (r275202)
• Accounted for hanging and each-line when blending text-interpolation (r275224)
• Added support for animating the vertical-align CSS property (r275160)
• Animated pseudo element style resolved against wrong parent style (r275277)
• Fixed interpolation of the caret-color CSS property (r275092)
• Computed style for a border-radius corner should never be 0px when the provided width isn't 0px (r275273)
• Enabled hanging and each-line keywords for the text-indent CSS property (r275199)
• Fixed align-content issues in Flexbox (r275416)
• Fixed max-height percentages getting wrongly resolved for replaced grid items in nested percentage flexboxes (r275758)
• Fixed min and max widths of grid affected by ancestor (r275754)
• Fixed initial horizontal scrollbar position when vertical scrollbar is on the left (r275811)
• Fixed max-content on tables with percentage cell widths (r275462)
• Improved interpolation of the shape-outside CSS property (r275015)
• Prevented negative heights in CSS Grid (r274933)
• Supported animation of the tab-size CSS property (r274939)
• Updated CSS Color 5 color-mix() implementation to match the latest draft spec (r274947)

JavaScript
• Fixed Intl.Locale to not assume is8Bit (r274784)
• Fixed Object.freeze(this) at the global scope to not lose a reference to a WatchpointSet (r274882)
• Fixed RegExp interpreter not to match against non-BMP characters with multiple dots (r274806, r274945)
• Fixed incorrect Array toString() if join() is not callable (r275544)

Web API

• Enabled the ability to prevent scrolling in Element.focus() (r274812)
• Implemented AbortSignal.abort() (r274773)
• Propagated user gestures through requestAnimationFrame just like setTimeout (r275187)
• ServiceWorker should save module scripts (r275751)
•
Rendering
• Fixed aspect-ratio to recompute on hover (r275377)
• Implemented text rendering on OffscreenCanvas in a Worker (r275420)

Wheel Events
• Allowed wheel events to trigger high frequency DisplayLinks (r275440)

Web Driver
• Fixed SendKeys on <input type="file"> returning element not found in some cases (r275050)

WebGL
• Enabled Metal ANGLE backend for WebGL (r274927)

WebRTC
• Implemented RTCDataChannel transfer (r274758)

WebCrypto
• Fixed WebCrypto to support AES-GCM 0 byte encryption (r275535)

Scrolling
• Fixed scrolling momentum with scroll-snap-type: x mandatory when the scroller scrolls vertically (r274853)
• Fixed scroll-snap-stop: always not respected during momentum scrolling (r274726)

Web Extensions
• Allow wss:// URL in content_security_policy to allow extension pages to use WebSocket connections

Versions:
• Downloads are for current version
• Safari Technology Preview 108 for OS X 10.14
• Safari Technology Preview 83 for OS X 10.13
• Safari Technology Preview 56 for OS X 10.12.6+

Requirements:
OS X 10.15+
Universal Binary