How would you convert a string into lowercase?

Peer-reviewed by HireXTech Technical Panel • Updated for 2025/2026 hiring • Editorial standards

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Core Competency

Assesses fundamental understanding of Python conventions, runtime behavior, and memory/performance considerations.

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Comprehensive Model Answer Verified Solution

We use the lower() method for this.

>>> 'AyuShi'.lower()

'ayushi'

To convert it into uppercase, then, we use upper().

>>> 'AyuShi'.upper()

'AYUSHI'

Also, to check if a string is in all uppercase or all lowercase, we use the methods isupper() and islower().

>>> 'AyuShi'.isupper()

False

>>> 'AYUSHI'.isupper()

True

>>> 'ayushi'.islower()

True

>>> '@yu$hi'.islower()

True

>>> '@YU$HI'.isupper()

True

So, characters like @ and $ will suffice for both cases

Also, istitle() will tell us if a string is in title case.

>>> 'The Corpse Bride'.istitle()

True

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