German cockroach vs American cockroach
These two are easy to mix up. Here's how to tell a german cockroach from a american cockroach, and whether either one bites or stings.
German cockroach
Blattella germanica
American cockroach
Periplaneta americana
≠The key differences
Smaller (12-16 mm), light brown with two dark parallel stripes on the pronotum; prefers indoor kitchens and is more commonly associated with apartments and restaurants.
⚖︎Side by side
| German cockroach | American cockroach | |
|---|---|---|
| To humans | Allergen carrier | Allergen carrier |
| Size | 12-16 mm body length | 30-50 mm body length |
| Colours | Light brown, Dark brown, Pale cream (underside) | Reddish brown, Dark brown, Pale yellow (pronotum margin) |
| Family | Ectobiidae | Blattidae |
| Habitat | Human dwellings: kitchens, bathrooms, behind appliances, inside cabinets, wall and floor voids, near plumbing and heat sources | Warm, humid places in and around human structures: basements, boiler rooms, sewers, drains, crawl spaces, commercial kitchens and garbage areas. |
| Range | Worldwide in temperate and tropical regions as a human commensal | Originally tropical; now cosmopolitan in warm buildings and sewer systems worldwide, common in temperate regions where it occupies heated structures. |
| Active | Primarily nocturnal; most active at night year-round in heated buildings | Nocturnal; active year-round indoors and in sewers, most visible at night. |
| Pest? | Yes | Yes |
🔍How to spot a german cockroach
- Small size (12-16 mm) and light brown colour with two dark parallel stripes on the pronotum
- Nocturnal behaviour; typically seen running, not flying, and hiding in cracks and behind appliances
- Both sexes have wings but poor flight; males are slightly more slender
- Nymphs are wingless and darker when newly hatched, becoming browner with molts
🔍How to spot a american cockroach
- Large reddish-brown body 30-50 mm long with fully developed wings in adults.
- Pronotum with a pale yellowish margin often visible as a ring around the shield behind the head.
- Smooth, shiny body with long antennae and spiny legs adapted for rapid running.
- Adults may fly short distances when disturbed (especially males).
?Frequently asked questions
What is the difference between a german cockroach and a american cockroach?
Smaller (12-16 mm), light brown with two dark parallel stripes on the pronotum; prefers indoor kitchens and is more commonly associated with apartments and restaurants.
Is a german cockroach or a american cockroach more dangerous?
German cockroach: Allergen carrier. American cockroach: Allergen carrier. German cockroaches do not bite or sting and are not venomous, but they contaminate food and surfaces with bacteria and allergens from droppings and shed skins. American cockroaches are not venomous and do not inject toxins, but they contaminate food and surfaces with bacteria and can trigger allergic reactions and asthma in sensitized people.
Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.