For the 2007 Kia Optima, the low-beam headlight uses an H11B bulb, while the high beam uses an H1. These are separate bulb sizes, so verify the bulb position before ordering or replacing a headlight bulb. The supplied fitment data does not list a fog-light bulb for this model year.
Other notable exterior bulbs include 2357A for the front turn signals and parking lights, 2357R for the brake and tail lights, and 2357 for the rear turn signals. The front and rear side markers use 168NA. Reverse lights and the center stop light use 921 bulbs.
Interior fitment includes 6418 for the dome and trunk lights. Map-light applications are listed as 194 and 7441, while courtesy and license-plate applications may use 168 or 917. Check the existing bulb and socket when more than one size is listed for an application.