Kajra Re (Hindi: कजरा रे, English: Oh, Kohl-Lined (Eyes)) is a song composed by Shankar-Ehsaan-Loy, written by Gulzar and sung by the playback singers Alisha Chinoy, Shankar Mahadevan and Javed Ali. It is from the 2005 film Bunty Aur Babli, starring Abhishek Bachchan, Rani Mukerji and Amitabh Bachchan. The song features Amitabh and Abhishek at a nightclub and Aishwarya Rai, making a special appearance in the film, sings for Amitabh, who joins her with Abhishek in the singing and dancing.

Kajra Re is inspired from a folk song from the Braj region, in which the celebrated kohl-lined eyes are Lord Krishna's, and belongs to the Qawaali genre with western fusion. The words "Tujhse milna purani dilli mein" have been rendered by Amitabh Bachchan. The trio have used sitar to make it sound more Indian. Amitabh Bachchan, after initially hearing the song, demanded a few changes, but the director, Shaad Ali, and producer, Aditya Chopra, convinced him against them. The song was composed in half a day. Alisha was chosen for the female vocals since her anglicized accent was meant to provide an essentially different intonation.

The song became extremely popular among the masses and was hugely successful on Indian music charts. The Hindustan Times described it as "the reinvention of the qawwali by Shankar-Ehsaan-Roy and Gulzar" and called it "the item number of the decade."Kajra Re featured on top in Rediffs 2005's list of top 5 songs. It also won the poll conducted by Planet Bollywood as the song of the year with a whopping 44%.

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