An accompanying music video was shot by Haruka Furuya; it features Amuro celebrating her birthday, and dancing in several colorful backgrounds and sceneries.
[4] CD Journal staff member's labelled the delivery as "hilarious", whilst calling it a "girly pop song".
[5] Lauren du Plessis from Electric Bloom magazine compared the composition to American recording artist Katy Perry, and called the production "fluffy".
[4] Similarly, Michael McCarthy, writing for Otakudx.com, compared the song to the same title tracks by Perry and American recording artist Selena Gomez, and likened the "feel good" lyrical content to "Celebration".
[7] Lyrically, the song celebrates Amuro's birthday and, according to McCarthy, highlights other anniversaries including weddings and parties.
[8] CD Journal staff member's was positive in their review, stating that whilst the song sounded "fresh", it still retained Amuro's signature "charm".
[9] An editor writing for Arama Japan was positive in their review, calling it a "sugary celebratory pop song".
Amuro's record labels: Dimension Point and Avex Trax, hired several dancers and extra actors to perform in the music video.
[18] Amuro found the dressing room scene to be difficult, as she had to rehearse dress-changes within a specific time frame so Furuya could be directed correctly.
The scene pans out, and has Amuro exit her home (which is near a flower bouquet stand) with her friends surprising her on her birthday.
The dancers and extra actors celebrate Amuro's birthday with balloons and confetti as she sings the song.
Japanese music editor Random J called Amuro in the video "too damn cute", and praised the production.
[26] "Birthday" was performed as one of the encore tracks to the concert tour, was released on the live DVD and Blu-Ray, entitled Namie Amuro Livegenic 2015–2016 (2016).