The primary language used for conducting the UPSC Civil Services Examination is English, but candidates are also permitted to use Hindi and several other regional languages for the examination. This bilingual approach allows for inclusivity, enabling candidates from different linguistic backgrounds to participate more comfortably. The option to choose the medium of examination enhances candidates' performance as it allows them to express their knowledge without the barrier of language. This flexibility reflects the commission's commitment to broadening access to civil services for all eligible aspirants across India.