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.
Head-to-head specifications
| Metric | Kia K5 | Lexus UX |
|---|---|---|
| Best combined MPG | 32 mpg | 43 mpg ✓ |
| Best city MPG | 29 mpg | 45 mpg ✓ |
| Best highway MPG | 38 mpg | 41 mpg ✓ |
| Lowest annual fuel costEPA estimate at 15,000 miles per year | $1,900 | $1,450 ✓ |
| Lowest CO2 output | 277 g/mi | 204 g/mi ✓ |
| Engines offered | SIDI & PFI, SIDI & PFI; Stop-Start, SIDI, SIDI; Stop-Start | SIDI & PFI; Hybrid, SIDI & PFI; Mild Hybrid, SIDI & PFI |
| Transmissions | Automatic (S8), Automatic (AM-S8) | Automatic (AV-S6), Automatic (variable gear ratios), Automatic (AV-S10) |
| Drivetrains | All-Wheel Drive, Front-Wheel Drive | All-Wheel Drive, Front-Wheel Drive |
| Fuel types | Regular | Regular |
| EPA class | Large Cars | Compact Cars |
| Years covered | 2021–2027 | 2019–2026 |
| Configurations on record | 26 | 24 |
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.
| Dimension | Kia K5 (2025) | Lexus UX (2026) | Difference |
|---|---|---|---|
| Length | 192.9 in | 177.2 in | 15.7 in |
| Width (excl. mirrors) | 73.2 in | 72.4 in | 0.8 in |
| Height | 56.7 in | 60.6 in | 3.9 in |
| Wheelbase | 112.2 in | 103.9 in | 8.3 in |
| Curb weight | 3,455 lbs | 3,516 lbs | 62 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