Kia K4 vs Lexus RC: Specs Compared

Also searched as Lexus RC vs Kia K4 specs — both orientations show this same side-by-side comparison.

The Kia K4 is the more efficient of the two: it reaches 34 mpg combined versus 26 mpg for the Lexus RC, a 8 mpg advantage and costs about $1,100 less per year to fuel.

Across 5 measured categories, the Kia K4 leads in 5. Figures are EPA test data, not manufacturer claims.

2025–2026

Kia K4

Midsize Cars · 8 configurations

34mpg combined (best)
All Kia K4 specs

2015–2025

Lexus RC

Subcompact Cars · 50 configurations

26mpg combined (best)
All Lexus RC specs

Head-to-head specifications

MetricKia K4Lexus RC
Best combined MPG34 mpg ✓26 mpg
Best city MPG30 mpg ✓22 mpg
Best highway MPG40 mpg ✓32 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$1,800 ✓$2,900
Lowest CO2 output264 g/mi ✓345 g/mi
Engines offeredSIDI, 2.0, with DMSSIDI & PFI
TransmissionsAutomatic (S8), Automatic (AV-S1)Automatic (S6), Automatic (S8)
DrivetrainsFront-Wheel DriveAll-Wheel Drive, Rear-Wheel Drive
Fuel typesRegularPremium
EPA classMidsize CarsSubcompact Cars
Years covered2025–20262015–2025
Configurations on record850

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

Kia K4 vs Lexus RC dimensions and size

The Kia K4 is 0.4 inches longer than the Lexus RC on a wheelbase 0.4 inches shorter, and 937 lbs lighter. Both clear the roughly 200 inches of usable length in a standard single garage bay.

Kia K4 versus Lexus RC exterior dimensions
DimensionKia K4 (2026)Lexus RC (2026)Difference
Length185.4 in185 in0.4 in
Width (excl. mirrors)72.8 in72.4 in0.4 in
Height55.9 in55.1 in0.8 in
Wheelbase107.1 in107.5 in0.4 in
Curb weight2,954 lbs3,891 lbs937 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.

Kia K4 vs Lexus RC: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Kia K4 burns about $1,800 of fuel annually against $2,900 for the Lexus RC. That $1,100 yearly gap compounds to roughly $5,500 over five years and $8,800 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 K4 leads in both cycles — 30 mpg city and 40 mpg highway against 22 and 32 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Kia K4 is recorded with 3 distinct engine configurations (SIDI, 2.0, with DMS), the Lexus RC with 1 (SIDI & PFI). Across 8 recorded Kia K4 configurations and 50 for the Lexus RC, 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 Kia K4 is offered with Front-Wheel Drive, the Lexus RC 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 Midsize Cars and Subcompact 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 K4 emits 264 g/mile of CO2 versus 345 g/mile for the Lexus RC. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

K4 vs RC: common questions

Which is better on gas, the Kia K4 or the Lexus RC?

The Kia K4 is the more efficient of the two: it reaches 34 mpg combined versus 26 mpg for the Lexus RC, a 8 mpg advantage and costs about $1,100 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Kia K4 runs about $1,800 a year in fuel at its most efficient configuration, versus about $2,900 for the Lexus RC — a difference of roughly $1,100 per year.

What engines do the K4 and RC offer?

Kia K4: SIDI, 2.0, with DMS. Lexus RC: SIDI & PFI.

Are they in the same vehicle class?

The EPA classifies the Kia K4 as Midsize Cars and the Lexus RC as Subcompact Cars, so they aren't a like-for-like match on size.

More K4 comparisons

More RC comparisons

Comparison id: kia-k4-vs-lexus-rc