Audi S3 vs Genesis G90: Specs Compared

Also searched as Genesis G90 vs Audi S3 specs — both orientations show this same side-by-side comparison.

The Audi S3 is the more efficient of the two: it reaches 27 mpg combined versus 21 mpg for the Genesis G90, a 6 mpg advantage and costs about $800 less per year to fuel.

Across 5 measured categories, the Audi S3 leads in 5. Figures are EPA test data, not manufacturer claims.

2015–2026

Audi S3

Subcompact Cars · 11 configurations

27mpg combined (best)
All Audi S3 specs

2017–2026

Genesis G90

Large Cars · 32 configurations

21mpg combined (best)
All Genesis G90 specs

Head-to-head specifications

MetricAudi S3Genesis G90
Best combined MPG27 mpg ✓21 mpg
Best city MPG23 mpg ✓18 mpg
Best highway MPG32 mpg ✓26 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,800 ✓$3,600
Lowest CO2 output331 g/mi ✓426 g/mi
Engines offeredSIDI, SIDI; Mild Hybrid, SIDI;SIDI & PFI, SIDI & PFI; Mild Hybrid, SIDI
TransmissionsAutomatic (AM-S7), Automatic (AM-S6)Automatic (S8)
DrivetrainsAll-Wheel DriveAll-Wheel Drive, Rear-Wheel Drive
Fuel typesPremiumPremium
EPA classSubcompact CarsLarge Cars
Years covered2015–20262017–2026
Configurations on record1132

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

Audi S3 vs Genesis G90 dimensions and size

The Genesis G90 is 30.7 inches longer than the Audi S3 on a wheelbase 21.7 inches longer, and 1,375.7 lbs heavier. At over 200 inches, the larger of the two is past the comfortable limit of a standard 192-inch single garage bay once you allow walking room.

Audi S3 versus Genesis G90 exterior dimensions
DimensionAudi S3 (2026)Genesis G90 (2026)Difference
Length177.2 in207.9 in30.7 in
Width (excl. mirrors)71.7 in58.7 in13 in
Height56.3 in76 in19.7 in
Wheelbase103.5 in125.2 in21.7 in
Curb weight3,483 lbs4,859 lbs1,376 lbs

Width excludes mirrors; add 8–12 inches for mirrors out. Figures are for the newest model year on record for each vehicle. See both drawn to scale.

Audi S3 vs Genesis G90: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Audi S3 burns about $2,800 of fuel annually against $3,600 for the Genesis G90. That $800 yearly gap compounds to roughly $4,000 over five years and $6,400 over eight — often more than the price difference between two trims of the same vehicle, and the single largest running-cost line item separating these two.

City and highway economy: the Audi S3 leads in both cycles — 23 mpg city and 32 mpg highway against 18 and 26 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Audi S3 is recorded with 3 distinct engine configurations (SIDI, SIDI; Mild Hybrid, SIDI;), the Genesis G90 with 3 (SIDI & PFI, SIDI & PFI; Mild Hybrid, SIDI). Across 11 recorded Audi S3 configurations and 32 for the Genesis G90, the wider the engine spread the more the real-world fuel efficiency depends on which version you actually buy, so check the specific model year and drivetrain rather than the headline number.

Drivetrain and class: the Audi S3 is offered with All-Wheel Drive, the Genesis G90 with All-Wheel Drive, Rear-Wheel Drive. All-wheel drive typically costs one to two mpg combined against the same vehicle in front- or rear-wheel drive, which is worth remembering when the gap between these two is small. The EPA classes them as Subcompact Cars and Large Cars respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.

Tailpipe emissions: at their cleanest configurations the Audi S3 emits 331 g/mile of CO2 versus 426 g/mile for the Genesis G90. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

S3 vs G90: common questions

Which is better on gas, the Audi S3 or the Genesis G90?

The Audi S3 is the more efficient of the two: it reaches 27 mpg combined versus 21 mpg for the Genesis G90, a 6 mpg advantage and costs about $800 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Audi S3 runs about $2,800 a year in fuel at its most efficient configuration, versus about $3,600 for the Genesis G90 — a difference of roughly $800 per year.

What engines do the S3 and G90 offer?

Audi S3: SIDI, SIDI; Mild Hybrid, SIDI;. Genesis G90: SIDI & PFI, SIDI & PFI; Mild Hybrid, SIDI.

Are they in the same vehicle class?

The EPA classifies the Audi S3 as Subcompact Cars and the Genesis G90 as Large Cars, so they aren't a like-for-like match on size.

More S3 comparisons

More G90 comparisons

Comparison id: audi-s3-vs-genesis-g90