"4 Hot Wave" is Japanese singer Koda Kumi's 32nd single on the Rhythm Zone label. It charted at #2 on Oricon and stayed on the charts for seventeen weeks. The sales for the single became her highest selling single, even surpassing the total sales of real Emotion/1000 no Kotoba in less than three weeks. It became her highest debut single and reclaimed the title of Highest Debut Sales Female Artists, previously held by Ayumi Hamasaki's Blue Bird.

4 hot wave is singer-songwriter Kumi Koda's thirty-second single and is her first quadruple a-side, with each song containing a corresponding music video. It hit #2 on the Oricon Weekly charts and reclaimed the Highest Debut Sales Female Artists from Ayumi Hamasaki.

The sales for 4 hot wave made it her highest selling single, even surpassing the total sales of real Emotion/1000 no Kotoba in less than three weeks. Within its first week, the single sold 207,484 copies, with 489,000 in total. Despite losing the number-one spot to KinKi Kids' Natu Moyou, 4 hot wave outsold them by over 80,000 copies. At the end of the year, the single ranked #2 on Highest Selling Single Female Artist, losing out to Naoru Amane's Taiyou no Uta, which was used in her film Midnight Sun.

Due to the single's success, it reclaimed the title of Highest Debut Sales Female Artists, from Ayumi Hamasaki's Blue Bird, which had originally taken the title from Koda Kumi's previous single, Koi no Tsubomi.

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