The Audi most often competes against the BMW 3-Series and Mercedes-Benz C Class—specifically the 340i and C43, respectively.
We'll concede that the Audi is faster, but the C43 and 340i are more enjoyable to drive, they're more visceral cars.
The styling on the C43 is somewhat divisive, and the BMW is just old at this point, but the Audi S4 stops short of delivering a knockout to either one.
The S4 beats the BMW on tech, but stops just short of beating the C43—we'd prefer a touchscreen to Audi's MMI.
The Cadillac and Lexus are both outliers in this race, neither offer a direct competitor but have refreshing approaches to luxury compact cars available.
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|2018 Audi A4Browse Used Listings||2018 BMW 3-SeriesBrowse Used Listings||2018 Cadillac ATSBrowse Used Listings||2018 Lexus ISBrowse Used Listings||2018 Mercedes-Benz C ClassBrowse Used Listings|
|21 MPG City / 37 MPG Hwy||20 MPG City / 43 MPG Hwy||19 MPG City / 32 MPG Hwy||17 MPG City / 33 MPG Hwy|
|Intercooled Turbo Premium Unleaded I-4||Intercooled Turbo Premium Unleaded I-4||N/A||Intercooled Turbo Premium Unleaded I-4||Intercooled Turbo Premium Unleaded I-4|
|Compact Cars||Compact Cars||N/A||Compact Cars||Compact Cars|
|2.0 TFSI ultra Premium S Tronic FWD||320i Sedan||N/A||IS 300 F Sport RWD||C 300 Sedan|
|Front Wheel Drive||Rear Wheel Drive||N/A||Rear Wheel Drive||Rear Wheel Drive|
|Auto-Shift Manual w/OD||Automatic w/OD||N/A||Automatic w/OD||Automatic w/OD|
|Detailed Spec Comparison|
|2018 Audi A4 vs. 2018 BMW 3-Series||2018 Audi A4 vs. 2018 Cadillac ATS||2018 Audi A4 vs. 2018 Lexus IS||2018 Audi A4 vs. 2018 Mercedes-Benz C Class|