Kidcore is a fashion style and internet aesthetic that celebrates the nostalgia and bright, playful imagery of childhood, primarily from the 1990s and early 2000s. It is characterized by the use of highly saturated primary colors, cartoon graphics, and elements drawn from children's toys and media. Originating on platforms like Tumblr in the mid-to-late 2010s, the aesthetic gained significant popularity on TikTok and Instagram around 2020, partly as a response to the need for comfort and escapism. Kidcore encourages a "more-is-more" approach to style, blending comfort with a sense of carefree, youthful fun.

The aesthetic is heavily influenced by Japanese street fashion styles like Decora , but is generally less elaborate and places a greater emphasis on comfort and accessibility. It is also related to the parallel Chinese trend of Dopamine Dressing .

The visual style of Kidcore is a direct reflection of its nostalgic themes, drawing heavily from the toys, media, and environments of a 1990s and early 2000s childhood. The aesthetic is dominated by a bright, saturated color palette with a strong emphasis on red, yellow, and blue. Its core motifs are sourced from this era, featuring characters from classic children's television and the distinct, vibrant artwork of brands like Lisa Frank and Sanrio. Imagery of iconic toys such as Furbies, Beanie Babies, and Tamagotchis is central to the style. The aesthetic also evokes the atmosphere of childhood through depictions of playgrounds, ball pits, and arts and crafts elements like alphabet blocks and stickers. This visual identity also extends to architecture, with a sub-style known as "Memphis Jr." or "Wonka Post-Modern" seen in the playful, geometric designs of children's stores from the period.

Kidcore fashion is defined by its use of bright, often primary, colors and a playful mix of textures and patterns, prioritizing comfort and a sense of fun. Staple garments often include graphic tees featuring characters from 90s cartoons, denim or corduroy overalls, and brightly colored knitwear like striped cardigans. The style embraces a "more-is-more" attitude through mismatched prints and tie-dye patterns. The look is completed with an array of toy-like accessories, such as handmade beaded friendship bracelets, plastic butterfly hair clips, scrunchies, and even colorful stickers worn on the face or body. Footwear remains comfortable and playful, with popular choices including colorful Converse sneakers, Crocs, and light-up shoes.