Kia K5 vs Lexus UX: Specs Compared

Also searched as Lexus UX vs Kia K5 specs — both orientations show this same side-by-side comparison.

The Lexus UX is the more efficient of the two: it reaches 43 mpg combined versus 32 mpg for the Kia K5, a 11 mpg advantage and costs about $450 less per year to fuel.

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

2021–2027

Kia K5

Large Cars · 26 configurations

32mpg combined (best)
All Kia K5 specs

2019–2026

Lexus UX

Compact Cars · 24 configurations

43mpg combined (best)
All Lexus UX specs

Head-to-head specifications

MetricKia K5Lexus UX
Best combined MPG32 mpg43 mpg ✓
Best city MPG29 mpg45 mpg ✓
Best highway MPG38 mpg41 mpg ✓
Lowest annual fuel costEPA estimate at 15,000 miles per year$1,900$1,450 ✓
Lowest CO2 output277 g/mi204 g/mi ✓
Engines offeredSIDI & PFI, SIDI & PFI; Stop-Start, SIDI, SIDI; Stop-StartSIDI & PFI; Hybrid, SIDI & PFI; Mild Hybrid, SIDI & PFI
TransmissionsAutomatic (S8), Automatic (AM-S8)Automatic (AV-S6), Automatic (variable gear ratios), Automatic (AV-S10)
DrivetrainsAll-Wheel Drive, Front-Wheel DriveAll-Wheel Drive, Front-Wheel Drive
Fuel typesRegularRegular
EPA classLarge CarsCompact Cars
Years covered2021–20272019–2026
Configurations on record2624

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

Kia K5 vs Lexus UX dimensions and size

The Kia K5 is 15.7 inches longer than the Lexus UX on a wheelbase 8.3 inches longer, and 61.7 lbs lighter. Both clear the roughly 200 inches of usable length in a standard single garage bay.

Kia K5 versus Lexus UX exterior dimensions
DimensionKia K5 (2025)Lexus UX (2026)Difference
Length192.9 in177.2 in15.7 in
Width (excl. mirrors)73.2 in72.4 in0.8 in
Height56.7 in60.6 in3.9 in
Wheelbase112.2 in103.9 in8.3 in
Curb weight3,455 lbs3,516 lbs62 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 K5 vs Lexus UX: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Lexus UX burns about $1,450 of fuel annually against $1,900 for the Kia K5. That $450 yearly gap compounds to roughly $2,250 over five years and $3,600 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 Lexus UX leads in both cycles — 45 mpg city and 41 mpg highway against 29 and 38 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Kia K5 is recorded with 4 distinct engine configurations (SIDI & PFI, SIDI & PFI; Stop-Start, SIDI), the Lexus UX with 3 (SIDI & PFI; Hybrid, SIDI & PFI; Mild Hybrid, SIDI & PFI). Across 26 recorded Kia K5 configurations and 24 for the Lexus UX, 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 K5 is offered with All-Wheel Drive, Front-Wheel Drive, the Lexus UX with All-Wheel Drive, 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 Large Cars and Compact 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 Lexus UX emits 204 g/mile of CO2 versus 277 g/mile for the Kia K5. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

K5 vs UX: common questions

Which is better on gas, the Kia K5 or the Lexus UX?

The Lexus UX is the more efficient of the two: it reaches 43 mpg combined versus 32 mpg for the Kia K5, a 11 mpg advantage and costs about $450 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Lexus UX runs about $1,450 a year in fuel at its most efficient configuration, versus about $1,900 for the Kia K5 — a difference of roughly $450 per year.

What engines do the K5 and UX offer?

Kia K5: SIDI & PFI, SIDI & PFI; Stop-Start, SIDI, SIDI; Stop-Start. Lexus UX: SIDI & PFI; Hybrid, SIDI & PFI; Mild Hybrid, SIDI & PFI.

Are they in the same vehicle class?

The EPA classifies the Kia K5 as Large Cars and the Lexus UX as Compact Cars, so they aren't a like-for-like match on size.

More K5 comparisons

More UX comparisons

Comparison id: kia-k5-vs-lexus-ux