elasticsearch/docs/reference/text-analysis/analysis-lowercase-tokenizer.md

navigation_title	mapped_pages
Lowercase	https://www.elastic.co/guide/en/elasticsearch/reference/current/analysis-lowercase-tokenizer.html

Lowercase tokenizer [analysis-lowercase-tokenizer]

The lowercase tokenizer, like the letter tokenizer breaks text into terms whenever it encounters a character which is not a letter, but it also lowercases all terms. It is functionally equivalent to the letter tokenizer combined with the lowercase token filter, but is more efficient as it performs both steps in a single pass.

Example output [_example_output_12]

POST _analyze
{
  "tokenizer": "lowercase",
  "text": "The 2 QUICK Brown-Foxes jumped over the lazy dog's bone."
}

The above sentence would produce the following terms:

[ the, quick, brown, foxes, jumped, over, the, lazy, dog, s, bone ]

Configuration [_configuration_13]

The lowercase tokenizer is not configurable.