# Normalizer **`class Normalizer(config)`** Bases: [`BatchedStep`](../technical/libnlp/steps/standard.md#squirro.lib.nlp.steps.batched_step.BatchedStep) The [`Normalizer`](#squirro.lib.nlp.steps.normalizers.Normalizer) step applies specific normalizations to fields for each [`Document`](../technical/libnlp/base.md#squirro.lib.nlp.document.Document). Parameters - `type` ([`str`](https://docs.python.org/3.11/library/stdtypes.html#str)) – Type of [`Normalizer`](#squirro.lib.nlp.steps.normalizers.Normalizer) (‘character’, ‘html’, ‘lowercase’, ‘punctuation’, or ‘stopwords’) - `fields` ([`list`](https://docs.python.org/3.11/library/stdtypes.html#list)`, ``[``]`) – List of fields to normalize - `input_fields` ([`list`](https://docs.python.org/3.11/library/stdtypes.html#list)`, ``None`) – List of fields to normalize from - `output_fields` ([`list`](https://docs.python.org/3.11/library/stdtypes.html#list)`, ``None`) – List of fields to normalize to