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<number>

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 <number> CSS data type represents a number, being either an integer, a number with a fractional component, or a base-ten exponent in scientific notation.

Syntax

The syntax of <number> extends the syntax of <integer>. A fractional value is represented by a . followed by one or more decimal digits, and may be appended to an integer. A <number> can also end with the letter e or E followed by an integer, which indicates a base-ten exponent in scientific notation. There is no unit associated with numbers.

As with integers, the first character of the number can be immediately preceded by - or + to indicate the number's sign: whether the number is positive or negative.

Interpolation

When animated, values of the <number> CSS data type are interpolated as real, floating-point numbers. The speed of the interpolation is determined by the easing function associated with the animation.

Examples

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Valid numbers

12          A raw <integer> is also a <number>.
4.01        Positive fraction
-456.8      Negative fraction
0.0         Zero
+0.0        Zero, with a leading +
-0.0        Zero, with a leading -
.60         Fractional number without a leading zero
10e3        Scientific notation
-3.4e-2     Complicated scientific notation

Invalid numbers

12.         Decimal points must be followed by at least one digit.
+-12.2      Only one leading +/- is allowed.
12.1.1      Only one decimal point is allowed.

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
number 1 12 1 2 1 18 4 10.1 1 1.0 4.4 1
scientific_notation 43 12 29 30 10.1 43 29 30 10.3 4.0 43 10.3

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/CSS/number