CSS Function
opacity()
The opacity() filter function applies transparency to an element's rendering, affecting both content and background.
Syntax
filter: opacity(amount)Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| amount | number | percentage | Yes | Opacity level: 0/0% (fully transparent) to 1/100% (fully opaque) |
Examples
Half transparent
Makes the element 50% transparent.
css
filter: opacity(0.5);Combined filters
Slightly transparent with a blur.
css
filter: opacity(0.8) blur(2px);Tailwind filter opacity
Tailwind's opacity-50 utility (uses the opacity property, not filter).
html
<img class="opacity-50" src="photo.jpg" />Browser Support
✓
Chrome
v18++
✓
Firefox
v35++
✓
Safari
v6++
✓
Edge
v12++
✓
Opera
v15++
Tailwind Equivalent
You can achieve similar results in Tailwind CSS using the following utility classes:
opacity-{value}: opacity-0, opacity-50, opacity-100, etc.Frequently Asked Questions
What is the difference between filter: opacity() and the opacity property?▼
filter: opacity() can be hardware-accelerated and combined with other filters in a single pipeline. The opacity property creates a new stacking context.
Does opacity affect child elements?▼
Yes. Both filter: opacity() and the opacity property affect the entire element including children. For background-only transparency, use rgba/hsla background colors.
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