What’s the distance of the 3 point line from the basketball hoop?

25 feet in pro 23.7 in college and 21 ft in HS
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24.7 feet which is pretty long
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It is about to change;
high school and college changes from 19' 9'' to 20' 9'' next year.

While the NBA 3 point line up top is 23' 9;'' and on the sides to give the players more room it is only 22' 6''.

That's why old cats like Robert horry and Bruce Bowen can only shoot from the baselines. Hope this help, check the link to full court dimensions.
References :
http://www.produnkhoops.com/support/guides/basketball_courts/court_dimensions.html

23 feet is the closest
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It's important to note that the 3 point arc is not the same distance from the center of the rim at all spots. This results from the fact that on the baseline, the 3 point arc begins with a straight line, before starting its curve. Once the curve begins, the distance stays consistent all the way around the arc.

Once the 3 point arc begins, the college and high school 3 point arc is 19.75 feet (19 feet 9 inches, or 237 inches).

The NBA distance is 23.75 feet (23 feet, 9 inches, or 285 inches). However, on the baselines, with a line drawn directly from the center of the rim to the sideline, the NBA distance is 22 feet (264 inches).
References :
http://www.betterbasketball.com/basketball-court-dimensions/