Web Platform Baseline Status Breakdown
Total Features: 1219
Categories:
All
CSS (102)
HTML elements (100)
Selectors (46)
JavaScript (43)
Forms (42)
WebGL extensions (37)
Text (26)
WebAssembly (22)
Media queries (21)
Scrolling (20)
Fonts (19)
Performance (19)
Arrays (17)
Layout (17)
HTML (16)
Progressive web app (15)
Typed arrays (14)
Units (14)
Canvas (13)
Color types (13)
Strings (13)
Background (12)
Media elements (12)
Security (12)
Animation (11)
Clipping, shapes, and masking (11)
Web components (11)
WebXR (11)
Typographic font features (10)
DOM (9)
Internationalization (9)
Iterators (9)
Reporting (9)
Text wrap (9)
Workers (9)
Clipboard (8)
CSS object models (7)
Containment (7)
Fetch (7)
JavaScript modules (7)
Print media (7)
Sensors (7)
Container queries (6)
Explicit defaults (6)
Image formats (6)
Landmark elements (6)
Multi-column (6)
Positioning (6)
Promises (6)
SVG (6)
Storage (6)
Streams (6)
Credential management (5)
Custom elements (5)
Font synthesis (5)
HTTP (5)
Lists (5)
Messaging (5)
Resource hints (5)
Ruby (5)
Selection (5)
Speech (5)
Transitions (CSS) (5)
View transitions (5)
Web audio (5)
WebGL (5)
Anchor positioning (4)
Cookies (4)
Counters (4)
File system access (4)
Flexbox (4)
Gamepad (4)
Grid (4)
Images (4)
Primitive types (4)
Regular expressions (4)
WebDriver (4)
WebRTC (4)
Blend mode (3)
Borders and outlines (3)
Geolocation (3)
Gradients (3)
Image scaling (3)
JSON (3)
Maps (3)
MathML (3)
Payments (3)
Reading order (3)
Scroll markers (3)
Transforms (3)
WebAuthn (3)
WebGPU (3)
White space (3)
Worklets (3)
XML (3)
Collections (2)
Compute pressure (2)
IndexedDB (2)
Parsing and serialization (2)
Resource integrity (2)
Sets (2)
Text fragments (2)
WebMCP (2)
CSS environment variables (1)
2026
4 features
• January 2026
2023
3 features
• December 2023
• November 2023
2022
1 features2020
1 features2017
1 features
• October 2017
Widely Available
The vw, vh, vmin, and vmax CSS viewport units are relative to the size of the viewport, and are used to size elements in relation to the viewport's dimensions.
Chrome
26
Firefox
19
Safari
7
Edge
16
Baseline Date: Oct 17, 2017
2015
4 features
• July 2015
Widely Available
The em CSS length unit is a font-relative length equal to the specified font size. In an element with a 2 inch font, 1em equals 2 inches.
Chrome
1
Firefox
1
Safari
1
Edge
12
Baseline Date: Jul 29, 2015