"Connect" (コネクト, Konekuto^?) is a pop song by the Japanese duo and idol unit ClariS, written by Shō Watanabe. It was released as the unit's second single on February 2, 2011 by SME Records. The song was used as the opening theme to the 2011 anime series Puella Magi Madoka Magica. A music video was produced for "Connect", directed by Takumi Shiga. The single peaked at No. 5 on Japan's weekly Oricon singles chart, and was later awarded a Gold Disc by the Recording Industry Association of Japan for having exceeded 100,000 copies shipped in a single year.

"Connect" is a J-pop song with instrumentation from piano, violin and drums. According to a book of sheet music published by Shinko Music Entertainment, it is set in common time and moves at a tempo of 175 beats per minute. Beginning in the D minor key, the introduction starts with only piano accompanying ClariS' vocals in the chorus melody. A bridge is used in G-flat major with added drums and violin to transition into the first verse in C minor, which shifts back to G-flat major with the chorus. After another bridge, still in G-flat major, this pattern is repeated for the second verse and chorus featuring the same music with different lyrics. The second key shift from C minor to G-flat major is the final key change of the song. A break is used to transition into a short third verse, followed by the chorus as the outro. A coda is used to close the song.

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