Safari for Developers

Leading performance. Great developer tools.
And a powerful new way to keep users engaged with your website.


CSS Regions New

Safari supports complex, magazine-like layouts for webpages. CSS Regions allow content in complex layouts to flow within different regions and still be associated.

CSS quotation marks New

CSS quotation marks are now language sensitive, allowing your webpages to display the right quotation marks for your language character set.

CSS Filters

CSS filters make it simple to create advanced filter and pixel effects such as blurs and gradients. CSS filters can vary brightness, adjust hues, invert colors, or convert elements to sepia or grayscale. Developers can combine filters and animate changes between them, while tapping into hardware acceleration for fast, smooth rendering.

CSS Animation

CSS animation, an open standard that brings a new level of interactivity to the web, lets web designers scale, rotate, fade, and skew web elements to create cutting-edge websites. Safari was the first web browser to support CSS animation.

CSS Effects

Pioneered by Safari, CSS effects help developers add polish to websites by stylizing images and photos with eye-catching gradients, precise masks, and stunning reflections that require only a few lines of code.

CSS3 Web Fonts

CSS3 web fonts allow web designers to create stunning websites using the fonts they prefer rather than restricting themselves to "web-safe fonts." Safari was the first web browser to automatically recognize websites that use custom fonts, downloading them as they're needed.

CSS3 Auto-Hyphenation

Safari allows developers to provide better reading experiences and text layouts with support for CSS3 auto-hyphenation.

CSS3 Vertical Text

Developers can use top-to-bottom text layouts in web pages, allowing for greater customization of websites in languages that use vertical text, such as Chinese and Japanese.

CSS3 Text Emphasis

With the text emphasis property, web pages can display emphasis marks commonly used in East Asian text.

CSS Canvas

Using CSS Canvas, web designers can position canvas elements anywhere an image can be placed using CSS. Safari was the first web browser to support CSS Canvas.


HTML5 Media Support

Websites can now deliver rich, interactive media as easily as they deliver images. The first browser to support HTML5 audio and video tags, Safari helps developers create media-rich sites that don’t require additional plug-ins. The media tags also offer a rich scripting API, allowing developers to create powerful new controls as well as controls that match the style of the page.

Full Screen for HTML5 Video

You can watch video embedded with the HTML5 <video> tag in full screen. Full-screen support allows standards-based video to deliver a first-class viewing experience.

Closed Captions for HTML5 Video

Safari has support for closed captions in HTML5 video. If an HTML5 video on a web page includes closed captions, simply click the CC button in the video controls to display them.

HTML5 Geolocation

With Safari support for HTML5 geolocation, you can choose to share your location with certain websites that use it to provide relevant information, such as maps or nearby businesses.

HTML5 Sectioning Elements

Support for article, aside, footer, header, hgroup, nav, and section elements allows developers to create advanced web designs with semantic markup.

HTML5 AJAX History

Support for HTML5 AJAX history allows web developers to build interactive AJAX applications that update dynamically but still work smoothly with the back and forward navigation buttons in Safari.

HTML5 Sandbox Attribute

With support for the sandbox attribute for iframe elements, Safari can restrict the actions of contents hosted inside an iframe. This makes iframes more secure by preventing them from running scripts or loading plug-ins that could deliver unwanted or deceptive content.

HTML5 Draggable Attribute

Safari makes it easier for developers to create web pages with drag-and-drop user interfaces for items like photos or images.

HTML5 Forms Validation

Safari can check the information in online forms to ensure that the format is correct before sending the information to the website’s server. If the wrong information is entered in an input field, Safari can inform you about the error right away.

HTML5 Ruby

Safari can display annotations alongside the main text in a web page, allowing pronunciation annotations in web pages that use Chinese, Japanese, or Korean characters.

HTML 4.01 Support

Safari supports HTML 4.01, the authoring language that defines the structure and layout of web documents.

HTML5 Offline Support

Web developers can create applications that you can use even when you don’t have access to the Internet. Thanks to HTML5 offline support, web applications that are stored on your computer are immediately accessible anytime. Along with the application, web developers can also choose to store the application’s data on your system, so you always have the information you need. Applications and data can be stored in a traditional SQL-like database serving as an application cache or in the familiar cookie format.

HTML5 Canvas

Originally invented by Apple for Dashboard, HTML5 Canvas technology allows web designers to specify an area in HTML that can be dynamically stylized by a JavaScript program. Safari was the first web browser to support HTML Canvas, and the standard is now supported by most popular browsers.

HTML5 Web Notifications

Websites can keep users up to date about breaking news, new messages, and other alerts. Website notifications appear in the upper-right corner of the screen with other notifications and in the new Notification Center in Mountain Lion. Extensions enabled in Safari can also send notifications.

Graphics, Fonts, and Text

Widow and orphan support New

With widow and orphan support, you can specify page breaks and avoid awkward pagination in webpage text.

Kerning and Ligatures New

Text in webpages automatically benefits from support for kerning and ligatures in Safari.

Sideways text orientation New

With Safari support for text-orientation: sideways, Safari supports vertical text layouts that have horizontal text within them, helpful for webpages in East Asian languages.

Hardware Acceleration

Hardware acceleration allows Safari to tap into graphics processing units to display computing-intensive graphics, so standards like HTML5 and CSS3 can deliver rich, interactive media smoothly in the browser. Safari also accelerates plug-in content.

Graphics Acceleration for HTML5 Canvas

With Safari, HTML5 Canvas elements on web pages take advantage of hardware acceleration, allowing faster performance for interactive graphics that are rendered natively in the browser.

Anti-Aliased Fonts

Thanks to the anti-aliasing algorithm in Safari, you enjoy crisp, gorgeous fonts. The algorithm preserves the subtleties of each font while rendering each character with a crispness that makes your favorite sites a pleasure to read.

Contextual Letters

In many fonts, letters may change their shape and spacing depending on their position in a word. For example, in languages like Arabic, a letter used in the middle of a word may be shaped differently from the same letter used at the end of a word. Safari recognizes many of these contextual letterforms when rendering different fonts and languages.

Color Profile Support

The only browser that color-corrects web images, Safari delivers vibrant, accurate color. Safari has supported International Color Consortium (ICC) profiles from day one, so the photos and images you see in your browser are as true to the originals as possible.


Support for the Web Open Font Format (WOFF) gives web designers and developers a wider range of typography options for websites.

International Web Content

Safari is designed to handle web content from all regions of the world, including a broad range of alphabets, number systems, writing directions, currencies, weights and measurements, date and time formats, and time zones.

IDN Support

Access sites with non-English web addresses. Safari offers Internationalized Domain Name (IDN) support, which allows web developers to use URLs that contain non-English letters and characters.

Unicode Support

Because Safari supports Unicode, the accepted international encoding standard, you can enjoy web content in any number of languages, including Arabic, English, and Japanese.

Right-to-Left Text

Safari supports multidirectional text rendering, allowing websites drafted in other languages to display characters from right to left.


Captions for video New

WebKit now supports out-of-band captioning on Mountain Lion and Lion. In-band subtitles are now supported on Mountain Lion.

High DPI for image-set New

Support for high-DPI with the image-set function makes it easier to specify when to use higher-resolution images for displays with high pixel density.

HTTP strict transport security New

Your website can now specify that only https should be used to connect.

Page visibility events New

Safari now supports the page visibility API.

Web Speech API

Support for the Web Speech API, Safari can convert text to speech and vice versa, allowing developers to create accessible, voice-driven web apps.

ARIA Support

Safari supports Accessible Rich Internet Applications (ARIA). The ARIA standard helps web developers make dynamic web content more accessible for people with disabilities. With ARIA, sites taking advantage of advanced technologies like AJAX and JavaScript can now easily interoperate with assistive technologies.

Closed Captions for HTML5 Video

Safari can now deliver an accessible video experience. If a video embedded in a web page using the HTML5 <video> tag includes closed captions, click the CC button in the video controls to display them.

HTML5 Timed Text Tracks

Developers can specify the timing of any text that appears with a media element, such as captions or subtitles.

HTML5 Media Synchronization

Safari supports web pages that coordinate the playback of multiple HTML5 media elements. Website developers can overlay a sign language interpretation track on a video track and keep the two in sync.

Safari Extensions

Easy to develop

Safari extensions are built with standard web technologies — HTML5, CSS3, and JavaScript. So if you can develop for the web, you’ll feel right at home writing extensions for Safari.

Built-in developer tools

Safari simplifies extension development with Extension Builder. Instead of manually entering your scripts, stylesheets, and commands in a complicated text file, you can select your extension resources visually in Extension Builder, a template that’s as easy to fill out as a form.

Safari Developer Program

Developers can create secure, standards-based extensions for Safari. Create buttons for the toolbar or make your own extension bar. Interact with web pages and change the way web content appears. The free Safari Developer Program includes everything you need to start creating extensions.

Signed and secured

Members of the Safari Developer Program receive a free digital certificate to sign Safari extensions. This ensures that any updates to your extension come from you and not a third party.

Safari Dev Center

The Safari Dev Center provides a range of technical resources for extension development, including sample code and programming and conversion guides to assist you with creating Safari extensions.
visit Safari Dev Center

More Features

Safari Push Notifications New

Keep users up-to-date with news and other alerts using Apple push notifications. Once users have signed up for notifications from your website in Safari on OS X Mavericks, you can send push notifications that appear just like Mac app notifications even when Safari isn’t running. Users can click the notification to launch your website in Safari. Learn more

Sticky positioning New

With sticky positioning, elements can remain fixed within the Safari window even as the user scrolls.

WebKit Icon


WebKit — the open source rendering engine introduced by Apple — powers Safari on OS X and iOS. WebKit features blazing performance and extensive standards support. And because it’s open source, developers can examine WebKit code and contribute to the community.

Web Audio API

Developers can create and customize audio effects in web applications with rich media content, such as games or instrument simulators. The Web Audio API provides finer-grained control over the timing of audio playback and allows developers to process audio sources from HTML5 media elements, create spatial sound effects, and synthesize and process audio directly in JavaScript.

Acid 2 Compliance

Designed by the Web Standards Project, Acid tests determine whether a web browser complies with emerging Internet standards. Acid 2 tests for compatibility with new features in the HTML, CSS, and PNG standards. Pioneering the standardization effort, Safari passed Acid 2 on October 27, 2005 — two and a half years before any other popular browser.

Acid 3 Compliance

Safari was the first web browser to pass Acid 3. Acid 3 tests a browser’s ability to fully render pages using the web standards used to build dynamic, next-generation websites, including CSS, JavaScript, XML, and SVG.

Formatted XML Files

When developers download unstyled XML files, Safari presents the information in a clear document tree format, making it easier to read.

Media Caching

Safari can store audio and video data for web applications that use the HTML5 application cache, allowing for offline media playback and better media performance when an Internet connection is slow.


Safari supports real-time push notifications from a server. Web applications that use EventSource can receive faster, more reliable communications from the website’s server.


With support for WebSocket, Safari has a speedy, two-way communication link with a web application’s server, so online activities like chatting are faster and require less bandwidth.


With support for Mathematical Markup Language (MathML), Safari allows developers to embed mathematical notation in a web page without using an image file.

ECMA 262 Version 5.1 Support NEW

Safari supports the latest edition of the JavaScript standard, ECMA 262 version 5.1, enabling the next generation of advanced, interactive web applications.

JSON Support

With native support for JavaScript Object Notation (JSON), Safari allows web applications that use JSON to run faster and more securely.

Full-Screen Web Pages

With the Full Screen JavaScript API, developers can create immersive web experiences without a plug-in.

SVG 1.1 Support

By taking advantage of the Scalable Vector Graphics (SVG) support in Safari, web developers can create fonts, graphic elements, and animations on the fly that look great no matter how large or small they are. For example, mapping sites often use SVG to draw driving directions based on your location and destination.

ICC Color Profile Support

Safari uses advanced color management technology to deliver web images with rich, accurate color. In fact, it was the first browser to support International Color Consortium (ICC) profiles and has done so from day one, so the photos and images you see in your browser stay true to the originals.

Plug-in Support

Plug-ins are add-ons that expand a browser’s capabilities. Because it supports the standard Netscape plug-in architecture, Safari works with the full range of popular Internet plug-ins, including Flash, Shockwave, and QuickTime.

Scriptable Plug-ins

Thanks to its support for scriptable plug-ins, Safari lets developers create plug-ins that interact with standard elements on a page. For example, a plug-in could allow you to customize the appearance of a car. As you add or remove options, the scriptable plug-in could update the sticker price of the car.

Java Support

With Java support in Safari, you can use web pages that incorporate Java plug-in content.

XML 1.0 Support

Extensible Markup Language (XML) is a popular open industry standard for creating, managing, and sharing structured data. Because native XML support is built into Safari, JavaScript programs can efficiently read XML data feeds.

LiveConnect Support

Safari supports LiveConnect to ensure compatibility with popular enterprise web applications. LiveConnect allows Java and JavaScript to work together to deliver a more seamless browsing experience.