# Incircle of a triangle Calculator

## Calculates the radius and area of the incircle of a triangle given the three sides.

 side a side b side c 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit inradius r diameter φ incircle area Sc triangle area St area ratio Sc/St
Incircle of a triangle
 [1-6] /6 Disp-Num5103050100200
[1]  2021/10/14 17:42   50 years old level / Self-employed people / Very /
Purpose of use
cutting a record (music) in the shape of a triangle, needed to figure out the size needed for roughly 6" diameter incircle
Comment/Request
would be useful to input the diameter of incircle needed, with the results being the length of the three sides.
[2]  2021/04/19 18:32   20 years old level / An engineer / Useful /
Purpose of use
Finding the inscribed circle of a boring bar so that it can be converted to an equivalent carbide insert
Comment/Request
really good calculator

other geometries would also be useful (i.e. parallelogram, I can find calcs that provide an exterior circle but non-that do interior)
[3]  2018/05/29 18:15   30 years old level / An engineer / Useful /
Purpose of use
Calculating useful area of patio shade.
Comment/Request
The inverse would also be useful but not so simple, e.g., what size triangle do I need for a given incircle area.
[4]  2018/03/12 02:01   60 years old level or over / An engineer / - /
Purpose of use
As the previous comment stated, this was used to find the circular radius of the USPS Medium Tube (which ironically is a triangular prism) for the purposes of shipping items of circular cross-section (cylinders). The answer was about 1.5 inches, so the "tubes" are way too small for the items I wanted to ship inside. But that''s perfect for blueprints, its designed application.
[5]  2017/06/11 09:21   30 years old level / A homemaker / Very /
Purpose of use
To see how big a triangular cabinet needs to be to store my dinner plates.
Comment/Request
Thanks!
[6]  2016/12/09 06:01   20 years old level / A homemaker / Very /
Purpose of use
Shipping large photo prints in triangular "tubes" and wanted to know the equivalent diameter when compared with actual circular tubes

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