How long do cornichons last?
Unopened, they keep in the cupboard for about 1 year. Once opened, in the fridge for about 1 month.
This refers to: Jarred cornichons.

Shelf life of cornichons at a glance
| Storage | Unopened | Opened |
|---|---|---|
| Cupboard | 1 year | – |
| Fridge | – | 1 month |
Refrigerate once opened and keep the cornichons covered with brine. Cloudy brine or mould means throw them out.
Past its date does not mean spoiled
These are guide values for food stored correctly. A best-before date is not a throw-away date: many products are still fine after it. Check how it looks, smells and tastes. Mould, an unusual smell or a bulging can are reasons to throw it away. A use-by date is different: do not eat the food after it.