A3 vs CT5
In the compact luxury car class, the A3 and the CT5 are natural rivals. The spec sheets tell two different stories. The A3’s strength is fuel economy & range; the CT5’s is engine & performance.
At a glance
- Engine & Performance CT5 wins
- Fuel Economy & Range A3 wins
- Space & Practicality Tie
- Off-road & Towing Tie
- Engine & Performance2.6
- Fuel Economy & Range6.7
- Engine & Performance5.0
- Fuel Economy & Range5.0
Spec scores (0 to 10) are calculated from manufacturer specs against other models in the same class. See how the formula works. They are not reviews or user ratings.
Key Differences
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The CT5 has 36 hp more power
It’s a lopsided result (237 hp for the CT5, 201 hp for the A3) and one of the main reasons to choose between them. Power is only part of the story; weight, gearing and torque delivery shape how quick a car feels.
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The CT5 has 37 lb-ft more torque
The spread here is large: 258 lb-ft on the CT5 versus 221 lb-ft on the A3. Expect to notice it. Electrified powertrains deliver torque instantly, so compare torque figures alongside the powertrain type.
-
The A3 has better fuel economy
Think of it as a tiebreaker rather than a deal-breaker: 28 mpg for the A3, 26 mpg for the CT5. Official figures rarely match real-world driving exactly, but the ranking between two cars tends to hold.
-
The A3 has better highway fuel economy
On paper, the A3 is a touch ahead here, listing 34 mpg against 32 mpg. The A3 uses less fuel on the highway, a real saving on road trips and long commutes.
Design & Size
Dimensions
| Spec | A3 | CT5 |
|---|---|---|
| Length | N/A (not specified) | 193.8 in |
| Width (no mirrors) | N/A (not specified) | 74.1 in |
| Height | N/A (not specified) | 57.2 in |
| Wheelbase | N/A (not specified) | 116 in |
Engine & Performance
CT5 leads
This is one of the CT5’s strongest areas. On engine & performance, the A3 falls well short. The CT5 steps ahead thanks to 36 hp more power. More power helps with merging, overtaking and climbing hills, especially with passengers and luggage on board. Net result: the CT5 leads this part of the comparison.
Total system output
A3: 201 hp CT5: 237 hp The CT5’s extra output gives it more in reserve when you need to get up to speed.
Torque
A3: 221 lb-ft CT5: 258 lb-ft More torque means stronger pulling from low speeds, which you feel when accelerating from a stop or climbing grades.
Fuel Economy & Range
A3 leads
No contest in fuel economy & range: the A3 is the stronger of the two. In its favor, the A3 has better fuel economy. Better combined fuel economy lowers your running costs every week, and the savings add up over years of ownership. The fuel economy & range verdict goes to the A3.
Fuel economy (combined)
A3: 28 mpg CT5: 26 mpg The A3 uses less fuel on the standard combined cycle, which matters most if you drive a lot.
Fuel economy (highway)
A3: 34 mpg CT5: 32 mpg Speed, wind and load affect highway use a lot, but the official rating is a fair comparison point.
Space & Practicality
Too close to call
The space & practicality specs are close enough that neither gets the point. If space & practicality was going to be your tiebreaker, you’ll need a different one.
Off-road & Towing
Too close to call
You can skip ahead if off-road & towing was your deciding factor: the two are evenly matched here. Treat off-road & towing as common ground and look elsewhere for the deciding factor.
Safety & Tech
There isn’t a number to compare on safety & tech, just names. Look at the rows below to see how the A3 and the CT5 differ.
Full Specifications
Engine & Performance
| Spec | A3 | CT5 |
|---|---|---|
| Powertrain | Gas | Gas |
| Engine | 2.0L turbo I4 | 2.0L turbo I4 |
| Total system output | 201 hp | 237 hp (winner) |
| Torque | 221 lb-ft | 258 lb-ft (winner) |
| Transmission | 7-speed dual-clutch (S tronic) | 10-speed automatic |
| Drivetrain | AWD (quattro) | RWD (AWD available) |
Fuel Economy & Range
| Spec | A3 | CT5 |
|---|---|---|
| Fuel economy (combined)EPA estimate where available | 28 mpg (winner) | 26 mpg |
| Fuel economy (city) | 24 mpg | 23 mpg |
| Fuel economy (highway) | 34 mpg (winner) | 32 mpg |
Space & Practicality
| Spec | A3 | CT5 |
|---|---|---|
| Seats | 5 seats | 5 seats |
| Cargo (behind rear seats) | N/A (not specified) | 11.9 cu ft |
Off-road & Towing
| Spec | A3 | CT5 |
|---|---|---|
| AWD / 4WD available | Yes | Yes |
Safety & Tech
| Spec | A3 | CT5 |
|---|---|---|
| Basic warranty | 4 yr / 50,000 mi | 4 yr / 50,000 mi |
Dimensions
| Spec | A3 | CT5 |
|---|---|---|
| Length | N/A (not specified) | 193.8 in |
| Width (no mirrors) | N/A (not specified) | 74.1 in |
| Height | N/A (not specified) | 57.2 in |
| Wheelbase | N/A (not specified) | 116 in |
Price
| Spec | A3 | CT5 |
|---|---|---|
| Starting MSRP | N/A (not specified) | $47,595 Priciest in class |
“N/A” means the manufacturer does not specify the value or we could not confirm it. Figures marked “manufacturer rating” are the maker’s own claims, not our measurements.
Which One Should You Buy?
Choose the A3 if…
- you want better combined fuel economy (28 mpg vs 26 mpg)
- you cover long highway distances (34 mpg vs 32 mpg on the highway)
- you’re comfortable with how Audi does things
Choose the CT5 if…
- you want more power (237 hp vs 201 hp)
- you want more pulling power from low speeds (258 lb-ft vs 221 lb-ft of torque)
- you trust Cadillac and want to keep things familiar
Also Compared
Frequently Asked Questions
Which is better for most people, the A3 or the CT5?
The A3 and the CT5 split the comparison (fuel economy & range for the A3, engine & performance for the CT5), so pick the strength you’ll use.
Executive Summary
I love a proper cross-brand matchup, and the A3 against the CT5 is exactly that. For me, the deciding factor is that only the A3 gives you better fuel economy. I don’t want to sell the CT5 short, though: it has 36 hp more power.
I’d steer fuel economy & range fans toward the A3 and engine & performance fans toward the CT5.
My pick: the A3 for fuel economy & range, the CT5 for engine & performance, and no wrong answer between them.
Personal opinion based on the data above. Your priorities may differ.