Click the "Select File" button above, and choose your NEC file.
You’ll see a preview, if available.
Click the "Convert file to..." button to extract text information.
Convert NEC to another file type
To convert NEC Antenna models to another format, you need 4NEC2 or other Cad software.
Convert a file to NEC
To convert other file formats to the "RF Simulation Data" file type, you need software like 4NEC2 or a similar tool.
About NEC files
The .NEC file format is a legacy-rooted, ASCII text-based input file used by the Numerical Electromagnetics Code (NEC) software suite for modeling wire and surface antennas. Originally developed at Lawrence Livermore National Laboratory, this format acts as a "card deck" of instructions, defining the 3D coordinates of wires, simulation frequencies, and ground parameters. While powerful for RF engineering and Ham radio simulations, the file itself is just a script; you cannot view the 3D antenna structure or radiation patterns without specialized simulation software like 4NEC2 or EZNEC. Users often struggle with the format's strict, column-sensitive syntax (a holdover from punch cards) and the inability to preview designs in standard CAD tools. To share the model logic, convert to PDF or TXT. To visualize the results for reports, use simulation software to export the 3D geometry and Far Field patterns to PNG, JPG, or DXF.
Convert.Guru analyzes your NEC file, detects the exact format, and lets you read the text inside.
If you want to convert NEC file to JS, TS, PY, JAVA, CPP, C, CS, PHP, RB, GO, RS or SWIFT, you can use 4NEC2 or similar software from the "Antenna Modeling Input" category. In the File menu, look for Save As… or Export….
To convert SH, PY, KT, PS1, SWIFT, LUA, PL, JAVA, SCALA, JS, VBS or TS files to NEC, try 4NEC2 or another comparable tool in the "Antenna Modeling Input" category.
The NEC Converter Story
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our NEC converter.