1.
thirty minutes; half an hour
A period of time equal to thirty minutes or half of one hour.
三十分 means thirty minutes or half an hour.
Pronunciation
Both さんじゅっぷん and さんじっぷん are correct. The さんじっぷん reading follows the traditional sound change pattern, while さんじゅっぷん is more common in modern speech.
Alternative expressions
Counting minutes
The counter 分 has irregular sound changes: