[2] The K4 adopts the brand's "Opposites United" design language, it has vertical headlights and taillights with "pronounced edges" in the lighting signature and hidden rear door handles.

The Sedan has fastback styling with a thick D-Pillar, whereas the Hatchback has a shooting brake design.

[3][4] The interior of the K4 has the Connected Car Navigation Cockpit operating system (debuted in the EV9) with two screens measures up to almost 30 inches (76 cm) when combined, two rows of physical controls for the important vehicle functions and a T-Bar gear lever (for the automatic transmission version) instead of a rotary selector.

Other features found in the K4 are the Digital Key 2.0 with Ultra Wideband which allows customers to use their compatible devices or an NFC-enabled smart card as a virtual key and the first Kia to debut Al Assistant voice control technology by saying "Hey Kia".

[6][7] The K4 was launched in Australia on 16 January 2025, with four trim levels: S, Sport, Sport+, and GT Line.