Freeform plugin unique submission amount I'm needing to get the unique entry submission amount for a value.

Example:
Item1, Item2, Item1, Item3, Item1

Would return:
3

I was able to use the workaround here Search/Filter Freeform submissions by field value to get the specific submission amount but only wanting to know the number of unique submission values.

Can anyone help?
Looks like there's a Craft 2 plugin that exposes PHP's array_unique method to Twig.

So to continue on the example you linked to, it would be something like this with that plugin installed:

{# Initiate the hash in which we'll store matching submissions. #}
{% set matchingSubmissions = [] %}

{#
    Loop through all submissions, checking if the specified field
    matches the desired value.
#}
{% for submission in submissions if submission.fieldWithValue == '123' %}

    {# If the field matches, add it to the hash #}
    {% set matchingSubmissions = matchingSubmissions|merge([submission.fieldWithValue]) %}

{% endfor %}

{# Count the size of the resulting hash and save it. #}
{% set totalUniques = matchingSubmissions|unique|length %}