Get started with Tekla Tedds API

Updated: 14 May 2020

In this guide you will go through how to get started with Tekla Tedds API and how to utilize existing code examples when creating your own code.

Use this guide to get started with Tekla Tedds API.


You need to have a Tekla Tedds license in order to use Tekla Tedds API. If you do not have a license yet, or you would like to develop and sell you applications for 3rd parties,  join Tekla Partners Program.

To join, fill out and submit an online application form.

Apply now

Get started

You can use the Tekla Tedds API with any programming language which supports COM (Component Object Model ). In this guide we are creating new .NET application project that references Tekla Tedds API.

For more information, check the Introduction to Tekla Tedds API.

If you want to automate a calculation, read first the Automating library calculations guide.

Create a new Microsoft Visual Studio project

To get started you will need to create an empty .NET application project in Microsoft Visual Studio. Follow the steps in this guide: Create a new project in Microsoft Visual Studio.

Install Tekla Tedds API and add assemblies as references

Tekla Tedds API package is available in Use NuGet Package Manager in Microsoft Visual Studio to install or update Tekla Tedds API package. After installation you can use Tekla Tedds API assemblies as references in your Microsoft Visual Studio project. 

  1. On the Tools menu, point on NuGet Package Manager and click Manage NuGet Packages for Solution.
  2. Click the Browse tab, on the search box, search TeklaTeddsAPI (no spaces) and click on the first result.  Use NuGet Package Manager to install Tekla Tedds API.
  3. On the Project window, select the projects where you want to add the references.
  4. From the Version list, select your Tekla Tedds API version. 
  5. Click Install. Tekla TeddsAPI packages appear on the Installed tab, and also Solution Explorer shows the added packages.

Use Tekla Tedds calculator

The Tekla Tedds API uses an out-of-process COM server TeddsCalc.exe which means it can be used from both 32-bit and 64-bit processes. 

  • If you're using a Microsoft .NET programming language, add a reference to Tedds.TeddsCalcIA.dll.
  • If you are using a programming language that only supports COM then reference TeddsCalc.tlb

Create an instance of the Calculator object or use the ProgId Tedds.Calculator.

To start using the Tekla Tedds calculator you must first initialize the Tekla Tedds system using Calculator.Initialize.  The arguments you need to pass will depend on your requirements. Refer to the Calculator.Initialize API Reference for more details.

Learn with code examples

  1. Take a look at the TeddsApiTester example. Watch the video that demonstrates the application.
  2. Download the source code
  3. View the code and try to understand what's going on
  4. Make some small changes to the code and run the application again
  5. Then, move on to CubeExampleAPI that shows you how to use the Tekla Tedds calculator to work out the volume of a cuboid. The code example is available in C#, VBA, and VB Script. You will learn three basic principles allowing you to start integrating Tekla Tedds into your own software solutions. 
  6. Next, learn how you can convert Tedds file to pdf by downloading the source code of TeddsTedToPdfConverter code example.


Use the examples as a starting point of your own Tekla Tedds applications. Download the source code and modify to fit your need.