[EucliDraw Logo: Pappus theorem]

Welcome to EucliDraw®

A program for dynamic Euclidean Geometry

logosm What is it?

EucliDraw®, abbreviated EUC, is a program that draws figures of plane Euclidean Geometry. It is the modern drawing instrument, simulating the paper surface, the ruler, the compass and dozens of other specialized tools, that enable you to draw complicated figures, instantly and with high precision. Apart from the ready-to-use tools, it embodies an integrated programming environment in which you can script and compile tools of your own invention. Thus, you can extend its possibilities, without limits, create collections of specialized tools and, from time to time, construct precise figures that nobody has ever seen.

EucliDraw is the result of a long period of development, initiated in 1990 at the University of Crete and continuing until today. A first static version of the program was published and is available as freeware since 1998, under the name Isoptikon. The motivation for the development of the program, besides the natural inclination of its creators to Geometry and Programming, was the desire to contribute to the relieving of Geometry. All of Mathematics but especially Euclidean Geometry has the character of a play of exceptional beauty. Besides it is also "unbounded". It can be developed in infinite directions and as far as one is willing to explore unknown areas. It is the intention of this program to stay as close as possible to these ideas: "play", "beauty" and "unboundedness". It is the privilege of the User to judge if we had succeeded in this undertaken. Our effort on these lines, though, will continue in the years to come.

logosm What does it do?

EucliDraw replaces the paper with the screen-surface of your computer and the pencil with the mouse. To construct a shape, you first choose a tool and then click and drag the mouse. Sometimes a single click on the object adds instantly some other significant shape, for example the mid-point of a segment, or the circumcircle of a triangle. The word "dynamic" means that the relations between shapes are preserved if, after their construction, you modify them. Thus, for example the medians of a triangle are correctly redrawn if you change the position or the shape of a triangle. This feature opens new possibilities to discover theorems. For example whatever modifications you do to your triangle on the screen, you see that the three medians meet always at a point. Here are some of the features of the program:


Download EucliDraw 2.5.1 (for Windows Vista, -7 and -8).

Download EucliDraw 2.5.1 (for Windows XP).

Installation Info After downloading the setup executable file, double-click on it to start the installation. This, besides EucliDraw, will install also the microsoft library vcredist_x86, needed by programms written in C++. After the installation put all your files and documents created by EucliDraw in the main folder cotaining the executable (or subfolders of it). If some menu-items are disabled or do not appear in the user interface, close EucliDraw and then double click on it to re-open but pressing simultaneously the CTRL key. Then go to Settings/Customize Menus .../Save and click OK. This action restores all menu-items and their functionality.

New Tools Select the menu-item: User-Defined/Coincidences... to view the dialog enabling the exploration of coincidences of points on lines, lines on points etc. Before to use it for the first time locate and read the relative pages in the help.