---id: environmenttitle: Environment Variables---WebdriverIO sets the following environment variables within every worker:## `NODE_ENV`Set to `'test'` if it's not already set to something else.## `WDIO_LOG_LEVEL`Can be set to values `trace`, `debug`, `info`, `warn`, `error`, `silent` to write logs with corresponding details. Has priority over the passed `logLevel` value.## `WDIO_WORKER_ID`An unique id that helps identify the worker process. It has format of `{number}-{number}` where the first number identifies the capability and the second the spec file that capability is running, e.g. `0-5` indicates a worker the first running the 6th spec file for the first capability.