Where each one leads
Audi A5
- On Canada's official test the most frugal 2026 Audi A5 uses 9.1 l/100 km, the 2019 Porsche Boxster S 9.9.
Porsche Boxster S
- New Porsche Boxster S cars registered in Europe in 2022 average 0 g/km of CO₂ on the WLTP test, against 167 for the Audi A5 in 2022.
Only measures that do not depend on how many cars were sold: pass and failure rates against cars of the same age, ratings, fuel use and CO₂. How we compare
At a glance
| Audi A5 | Porsche Boxster S | |
|---|---|---|
| Model years in the US safety record | 2008–2026 | 2000–2014 |
| New cars registered in Europe | 265,785 (2010–2022) | 6,932 (2010–2022) |
| Licensed in the United Kingdom | 130,463 | — |
| On the road in the Netherlands | 6,562 | — |
| In traffic in Finland | 2,687 | — |
EEA new-car registrations (CC BY 4.0) · DVLA licensed vehicles (OGL v3.0) · RDW (CC0) · Traficom (CC BY 4.0) · generations: Wikidata (CC0).
Reliability and problems
| Audi A5 | Porsche Boxster S | |
|---|---|---|
| UK MOT first-time pass rate | 79% | — |
| … against cars of the same age | +8% | — |
| New York safety inspections failed | 1.0% | — |
| … against cars of the same year | −45% | — |
| Illogical odometer records (NL) | 2.7% | — |
| US owner complaints | 325 | 16 |
| Most complaints about | Electrical system | Engine and engine cooling |
| Model year with most complaints | 2020 (60) | 2003 (7) |
| US recall campaigns | 19 | 5 |
| Manufacturer service bulletins | 13,501 | 1,901 |
Complaint, recall and bulletin counts grow with the number of cars sold and are not adjusted for it. UK MOT: DVSA anonymised MOT results (OGL v3.0); New York: DMV inspections; complaints, recalls, bulletins and investigations: NHTSA (public domain); odometer: RDW (CC0).
Fuel, emissions and price
| Audi A5 | Porsche Boxster S | |
|---|---|---|
| Official combined fuel use, Canada | 9.1 l/100 km (2026) | 9.9 l/100 km (2019) |
| Real-world use in Europe, diesel hybrid | 6.9 l/100 km | — |
| Real-world use in Europe, petrol hybrid | 8.3 l/100 km | — |
| Real-world use in Europe, diesel | 6.5 l/100 km | — |
| Official CO₂ of new cars in Europe | 167 g/km | 0 g/km |
| Average power of new cars in Europe | 165 kW (221 hp) | 360 kW (483 hp) |
| Average mass in running order | 1,715 kg | 1,755 kg |
| Dutch list price when new (median) | €63,628 | — |
| Average odometer in Finland | 250,000 km | — |
Canada: NRCan Fuel Consumption Ratings, most frugal version of the latest year (OGL Canada). Europe: EEA monitoring of new-car CO₂ and on-board fuel meters (OBFCM), CC BY 4.0. Price: RDW catalogue price (CC0). Finland: Traficom (CC BY 4.0).