


Describe the difference between `==` and `===` in JavaScript (Oops, wrong language - stick to CSS)
Jul 19, 2025 am 02:15 AMThere are no == or == operators in CSS, they belong to programming languages such as JavaScript. CSS uses selectors and properties to apply styles, rather than comparisons or evaluations. 1. The attribute selector [attr=value] is used for exact matches, similar to strict matches ===; 2. Use ~=, |=, ^=, $=, *=, etc. to achieve partial or fuzzy matches, similar to the behavior of loose matches ==. Choose the right matching method according to your needs to ensure accuracy and performance.
Whoops! You mentioned CSS, so let's forget JavaScript for a moment — in CSS, we don't have ==
or ===
. Those operators belong to programming languages like JavaScript, not CSS.

CSS is a styling language, not a programming one. It doesn't do comparisons or evaluations like that. Instead, it uses selectors and properties to apply styles.
So if you're wondering about something similar in CSS, maybe you're thinking of attribute selectors or how values are matched in rules.

Here's what might be useful:
Attribute Selector: Exact Match [attr=value]
This matches elements where the attribute value exactly matches a specified value.

input[type="text"] { border: 1px solid blue; }
This will only target <input>
elements with type="text"
exactly — not type="password"
or anything else.
- If you remove the quotes or use different syntax (like
~=
or^=
), the behavior changes. - This is some analogous to strict matching, like
===
, since it looks for an exact match.
Partial or Fuzzy Matching with Attribute Selectors
There are several variations that act more loosely, similar to how ==
can sometimes cast values in JavaScript:
-
[attr~=value]
– matches if the attribute contains the value as one of a space-separated list. -
[attr|=value]
– matches if the attribute starts with the value followed by a hyphen. -
[attr^=value]
– matches if the attribute starts with the given value. -
[attr$=value]
– matches if the attribute ends with the given value. -
[attr*=value]
– matches if the attribute contains the given substring anywhere.
These behave more like loose matching — not strict equality, but flexible pattern matching.
When to Use What?
Use the exact match [attr=value]
when you need precision — for example, applying styles only to checkboxes that are marked as required.
Use partial matchers like *=
or ^=
when you want flexibility — such as styling all links that start with "https://".
- Think about specification and performance too:
- Exact matches are usually faster and clearer.
- Overusing complex attribute selectors may slow down rendering slightly on large pages.
So while CSS doesn't have ==
or ===
, understanding how attribute selectors work gives you similar control over matching conditions. Just keep in mind that they're used for selecting HTML elements based on their attributes, not for evaluating truth like in JS.
Basically that's it.
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