Plugin to say this much minute read on article blog page

Question

Is there any plugin to say this article is 2 min read  or blah minute read.

So depending upon content length time is displayed on article listing page and article page itself.

I am using blog article plugin for blog posts.

Comments

The blog content is a string. You can use PHP function to count words in a string
str_word_count(string,return,char)

Next, is to do a math floor calculation.

Words in a 1 minute speech 130 words.
Words in a 2 minute speech 260 words.
Words in a 3 minute speech 390words.
Words in a 4 minute speech 520words.
Words in a 5 minute speech 650words.
....

You may compose the formula yourself.