Im Nayeon was met with generally favorable reviews from critics, who praised its fun and catchy production and its way of blending various genres with pop music.

In the United States, it became the first album by a South Korean soloist to reach top ten on the Billboard 200 with over 52,000 pure physical sales.

Additionally, the EP was certified 2× Platinum by the Korea Music Content Association (KMCA) for selling over 500,000 physical copies.

[2] It was accompanied by a teaser image featuring a close-up shot of what appears to be a coffee table, with trinkets such as bottles of nail polish, jewellery and a cup of tea strewn across.

[3] Specifics about Im Nayeon and its impending release were also unveiled in the following weeks, with worldwide pre-orders for the mini-album starting on May 24.

[9] Nayeon worked with many notable names, including, Jade Thirlwall, Kenzie, LDN Noise, The Stereotypes, and American singer-songwriter Destiny Rogers.

[10][11] The first half of the EP is described as "wonderfully luminescent and colourful," that revolves around more upbeat production, such as dance and disco-pop sounds, with lyrics talking about confidence, " glowing happiness in newfound romance," and pursuing one's own feelings, while the second half is more mature, chill, and gentle, focusing more on R&B, jazzy, and ballad production, with lyrics that deal with inner anxieties while being in a relationship, worries, stress and, a state after a breakup.

[16] Characterized by bright beats, live instruments such as bass, guitar, and horn,[14][15] winding high notes, and a variety of ad libs.

[12][18] The lyrics "explored the flirtatious and accrescent sentiments of romance using onomatopoeia to portray popping a lover’s heart like a bubble.

"[12] The closing track, “Sunset," is a chill and jazzy song that incorporates the production of strings, a gentle tempo, keyboards, and bass.

[23] NME's Rhian Daly gives four stars out of five, highlighting its showcase of her pop brilliance and songwriting talent, despite staying close to Twice's sound.

Praising its way of blending pop production with various genres, writing, "IM NAYEON has set the standard for what’s to come and what to look out for with future solo projects from twice".

[28] On the US Billboard 200, the EP peaked at number 7 with pure 52,000 copies sold, making Nayeon the first South Korean soloist to enter the top 10 and highest selling female act of the year upon its release.