48 lines
1.4 KiB
Markdown
48 lines
1.4 KiB
Markdown
---
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title: What is the difference between Python's equality operators?
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shortTitle: Python equality operators
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type: question
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tags: python,type,comparison
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expertise: beginner
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author: maciv
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cover: blog_images/umbrellas.jpg
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excerpt: Python provides two distinct comparison operators for different task. Stop mixing them up using this quick guide.
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firstSeen: 2021-01-28T11:00:00+02:00
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lastUpdated: 2021-06-12T19:30:41+03:00
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---
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Python provides two very similar equality operators used for comparisons:
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- The double equals (`==`), also known as the equality operator
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- The `is` keyword, also known as the identity operator
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Although similar to one another, the double equals (`==`) and the `is` keyword are used for different comparison purposes and yield different results.
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The main difference between the two is that the `is` keyword checks for reference equality while the double equals (`==`) operator checks for value equality. In other words, `is` will return `True` if two variables both refer to the same object in memory (aka. identity), whereas the double equals operator will evaluate to `True` if the two objects have the same value.
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Here are some examples to clear up any confusion:
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```py
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a = [1, 2, 3]
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b = a
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c = [x for x in a]
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print([
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a == b, # True
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a is b, # True
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a == c, # True
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a is c # False
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])
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x = 'hi'
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y = x
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z = 'HI'.lower()
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print([
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x == y, # True
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x is y, # True
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x == z, # True
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x is z # False
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])
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```
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