Fuel consumption: 9 of 9 variants rated.
| # | Variant | Year | Body | Fuel | Fuel consumption |
|---|---|---|---|---|---|
| 1 | Opel Karl Rocks 1.0 Online Edition | 2017 | Hatchback | Petrol | 5.1 l/100km (55.4 mpg UK · 46.1 mpg US) |
| 2 | Opel Karl 1.0 120 Jaar Edition | 2019 | Hatchback | Petrol | 4.9 l/100km (57.6 mpg UK · 48.0 mpg US) |
| 3 | Opel Karl 1.0 Innovation | 2016 | Hatchback | Petrol | 4.9 l/100km (57.6 mpg UK · 48.0 mpg US) |
| 4 | Opel Karl 1.0 Edition | 2015 | Hatchback | Petrol | 4.9 l/100km (57.6 mpg UK · 48.0 mpg US) |
| 5 | Opel Karl 1.0 Cosmo | 2015 | Hatchback | Petrol | 4.4 l/100km (64.2 mpg UK · 53.5 mpg US) |
| 6 | Opel Karl Rocks 1.0 Online Edition | 2017 | Hatchback | Petrol | 4.3 l/100km (65.7 mpg UK · 54.7 mpg US) |
| 7 | Opel Karl 1.0 Edition | 2016 | Hatchback | Petrol | 4.3 l/100km (65.7 mpg UK · 54.7 mpg US) |
| 8 | Opel Karl 1.0 Innovation | 2016 | Hatchback | Petrol | 4.3 l/100km (65.7 mpg UK · 54.7 mpg US) |
| 9 | Opel Karl 1.0 Selection | 2015 | Hatchback | Petrol | 4.1 l/100km (68.9 mpg UK · 57.4 mpg US) |