Audi S3 vs Kia Forte: Specs Compared

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

The Kia Forte is the more efficient of the two: it reaches 35 mpg combined versus 27 mpg for the Audi S3, a 8 mpg advantage and costs about $1,050 less per year to fuel.

Across 5 measured categories, the Kia Forte 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

2015–2024

Kia Forte

Midsize Cars · 60 configurations

35mpg combined (best)
All Kia Forte specs

Head-to-head specifications

MetricAudi S3Kia Forte
Best combined MPG27 mpg35 mpg ✓
Best city MPG23 mpg31 mpg ✓
Best highway MPG32 mpg41 mpg ✓
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,800$1,750 ✓
Lowest CO2 output331 g/mi256 g/mi ✓
Engines offeredSIDI, SIDI; Mild Hybrid, SIDI;SIDI, 2.0, 1.8
TransmissionsAutomatic (AM-S7), Automatic (AM-S6)Automatic (AM-S7), Automatic (variable gear ratios), Manual 6-spd
DrivetrainsAll-Wheel DriveFront-Wheel Drive
Fuel typesPremiumRegular
EPA classSubcompact CarsMidsize Cars
Years covered2015–20262015–2024
Configurations on record1160

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

Audi S3 vs Kia Forte dimensions and size

The Kia Forte is 5.5 inches longer than the Audi S3 on a wheelbase 2.8 inches longer, and 714.3 lbs lighter. Both clear the roughly 200 inches of usable length in a standard single garage bay.

Audi S3 versus Kia Forte exterior dimensions
DimensionAudi S3 (2026)Kia Forte (2024)Difference
Length177.2 in182.7 in5.5 in
Width (excl. mirrors)71.7 in70.9 in0.8 in
Height56.3 in56.7 in0.4 in
Wheelbase103.5 in106.3 in2.8 in
Curb weight3,483 lbs2,769 lbs714 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 Kia Forte: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Kia Forte burns about $1,750 of fuel annually against $2,800 for the Audi S3. That $1,050 yearly gap compounds to roughly $5,250 over five years and $8,400 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 Kia Forte leads in both cycles — 31 mpg city and 41 mpg highway against 23 and 32 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 Kia Forte with 3 (SIDI, 2.0, 1.8). Across 11 recorded Audi S3 configurations and 60 for the Kia Forte, 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 Kia Forte with Front-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 Midsize 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 Kia Forte emits 256 g/mile of CO2 versus 331 g/mile for the Audi S3. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

S3 vs Forte: common questions

Which is better on gas, the Audi S3 or the Kia Forte?

The Kia Forte is the more efficient of the two: it reaches 35 mpg combined versus 27 mpg for the Audi S3, a 8 mpg advantage and costs about $1,050 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Kia Forte runs about $1,750 a year in fuel at its most efficient configuration, versus about $2,800 for the Audi S3 — a difference of roughly $1,050 per year.

What engines do the S3 and Forte offer?

Audi S3: SIDI, SIDI; Mild Hybrid, SIDI;. Kia Forte: SIDI, 2.0, 1.8.

Are they in the same vehicle class?

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

More S3 comparisons

More Forte comparisons

Comparison id: audi-s3-vs-kia-forte