Hello @p1c2u,

Thanks a lot for the response!
I checked the 0.19.1 release, and the issue in #821 was indeed solved.
Unfortunately the question in this discussion still exists.
I checked the source code, under openapi_core.unmarshalling.schemas.unmarshallers.SchemaUnmarshaller.find_format

for schema in self.schema_validator.iter_valid_schemas(value):
    schema_validator = self.schema_validator.evolve(schema)
    primitive_type = schema_validator.get_primitive_type(value)

    if primitive_type != "string":
        continue

    if "format" in schema:
        return str(schema.getkey("format"))

return None

I believe it is the if primitive_type != "string": condition makes the number type data can not be processed by the extra_format_unmarshaller defined by users.

I am wondering will the function be open in the future?

BTW many thanks for releasing the solution for #821 in short period!

The condition was set to simplify the process otherwise we would have to pass type for each format unmarshaller. I hope in future we can support all types.