LEVEL5 -judgelight-

"LEVEL5 -judgelight-" is a 2010 single by fripSide, released as the duo's fourth single through Geneon Universal Entertainment. It opened the television anime A Certain Scientific Railgun, a J.C.Staff production, as the series' first opening theme. The release also appeared as LEVEL5-judgelight- - EP and included the B-side "memory of snow."

With lyrics by Yoshino Nanjo and Satoshi Yaginuma and music composed and arranged by Yaginuma, the song pushes fripSide's electronic J-pop style toward bright trance textures. Fast programmed beats, layered synthesizers, and a clean, urgent vocal line give the track a strong sense of motion, while the chorus expands in width rather than weight.

That balance of precision and lift suits Academy City's science-centered setting, where ordered systems and sudden conflict exist side by side. The single performed strongly, reaching No. 4 on Oricon's weekly singles chart and remaining on the chart for 13 weeks. "LEVEL5 -judgelight-" was later included on the album infinite synthesis 1.