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The block-size CSS property defines the horizontal or vertical size of an element's block, depending on its writing mode. It corresponds to either the cssxref width or the cssxref height property, depending on the value of cssxref writing-mode .
Last updated on : 2023-02-27
Browser Versions
IE
Edge
Firefox
Chrome
Safari
Opera
Fully Supported
Partially
No Support
block-size on IE is not supported on any IE versions.
block-size on Edge is fully supported on 79-110, and not supported on 12-18 Edge versions.
block-size on Firefox is fully supported on 41-112, and not supported on 2-40 Firefox versions.
block-size on Chrome is fully supported on 57-113, and not supported on 4-56 Chrome versions.
block-size on Safari is fully supported on 12-16, partially supported on null-null, and not supported on 0-11 Safari versions.
block-size on Opera is not supported on any Opera versions.
block-size on Safari on iOS is fully supported on 12-16, and not supported on 3-11 Safari on iOS versions.
block-size on Android Browser support is currently unknown.
block-size on Opera Mobile is not supported on any Opera Mobile versions.
block-size on Chrome for Android is fully supported on all Chrome for Android versions.
block-size on Firefox for Android is fully supported on all Firefox for Android versions.
block-size on Samsung Internet is fully supported on 5-19, and not supported on 4-4 Samsung Internet versions.
Data sourced from
Overall Browser Compatibility Score
Note:block-size shows a browser compatibility score of 67. This is a collective score out of 100 to represent browser support of a web technology. The higher this score is, the greater is the browser compatibility. The browser compatibility score is not a 100% reflection for every browser and the web technology support. However, it does give you an estimate on how much you should rely on a particular web technology in terms of browser compatibility.
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