"I Can't Explain" is a song by the English rock band The Who, written by Pete Townshend, and produced by Shel Talmy. The song was issued as a single in December 1964 in the United States and on 15 January 1965 in the United Kingdom.

"I Can't Explain" was the A-side of the group's first single released under the name The Who—their previous single, "Zoot Suit" / "I'm the Face," was released under the name The High Numbers. In the album's liner notes, Townshend noted the song's similarity to the contemporaneous hit single "All Day and All of the Night" by The Kinks: "It can't be beat for straightforward Kink copying. There is little to say about how I wrote this. It came out of the top of my head when I was 18 and a half." In a 1994 issue of Q magazine, Roger Daltrey echoed Townshend's comments regarding The Kinks' influence on the writing of the song:

We already knew Pete (Townshend) could write songs, but it never seemed a necessity in those days to have your own stuff because there was this wealth of untapped music that we could get hold of from America. But then bands like The Kinks started to make it, and they were probably the biggest influence on us – they were certainly a huge influence on Pete, and he wrote 'I Can't Explain', not as a direct copy, but certainly it's very derivative of Kinks music.

In a May 1974 interview with Creem Magazine, Jimmy Page claimed to have played rhythm guitar on the song as a session guitarist and this was confirmed by Pete Townshend and record producer Shel Talmy. According to those working on the recordings, however, Page's session contribution is believed to have not made the final cut, and has been brought into question. The Who have used "I Can't Explain" throughout many of their live performances, often as the opener, and it continues to be a staple today.

In a 2015 interview with Rolling Stone Magazine, Pete Townshend referred to "I Can't Explain" as "a song, written by some 18-year-old kid, about the fact that he can't tell his girlfriend he loves her because he's taken too many Dexedrine tablets."

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