MongoDB case-insensitive search

case insensitive (not comparable) (computer science) Treating or interpreting upper- and lowercase letters as being the same .

Comparing strings in a case insensitive manner means to compare them without taking care of the uppercase and lowercase letters. To perform this operation the most preferred method is to use either toUpperCase() or toLowerCase() function .

If you want only part of the regex to be case insensitive (as my original answer presumed), then you have two options:

By default, the comparison of an input string with any literal characters in a regular expression pattern is case sensitive , white space in a regular expression pattern is interpreted as literal white-space characters, and capturing groups in a regular expression are named implicitly as well as explicitly.15 Eyl 2021

All modes after the minus sign will be turned off. E.g. (? i-sm) turns on case insensitivity, and turns off both single-line mode and multi-line mode . Not all regex flavors support this.