NCD to TXT Converter

NCD to TXT Conversion Explained

Converting .NCD (Numeric Control Drill) files to .TXT (plain text) changes machine-readable PCB manufacturing instructions into a universally accessible text format. .NCD files, often formatted in the Excellon standard, contain X and Y coordinates and tool codes (T-codes) used by CNC machines to drill holes in Printed Circuit Boards.

Because .NCD files are already encoded in ASCII, you can often open them directly in a text editor. However, a true conversion to .TXT involves parsing the raw G-code and extracting the drill coordinates and tool sizes into a clean, human-readable list. People convert .NCD to .TXT to review drill data, generate documentation, or import hole coordinates into generic spreadsheet software. The main trade-off is functionality: extracting the data into plain text removes the specific syntax required to drive a CNC drill. If your goal is PCB fabrication, you should not convert the file.

Typical Tasks and Users

• PCB Designers: Reviewing tool sizes and hole counts in a standard text editor before sending manufacturing files to a fabrication house.
• CAM Engineers: Troubleshooting coordinate offsets, missing drill hits, or scaling issues without opening heavy CAM software.
• Software Developers: Converting drill data into a simplified text format to feed into custom scripts, databases, or quality assurance tools.
• Technical Writers: Including drill specifications and coordinate tables in plain text documentation.

Software & Tool Support

Because .NCD files are ASCII-based, they interact well with both specialized engineering software and basic text tools.

• PCB & CAM Software: Programs like KiCad, Altium Designer, and Gerbv natively generate, read, and export .NCD files.
• Text Editors: Notepad++, Visual Studio Code, and standard OS text editors (Notepad, TextEdit) can open both .NCD and .TXT files for raw viewing.
• Scripting Languages: Python (using libraries like gerber) can parse .NCD files and output formatted .TXT files.

Pros and Cons of the Conversion

Pros:

• Universal Compatibility: .TXT files open on any operating system without specialized PCB software.
• Readability: A parsed .TXT file translates cryptic G-code (e.g., T01, X01500Y02000) into clear measurements (e.g., Tool 1: 0.8mm, X: 1.5in, Y: 2.0in).
• Data Portability: Plain text is easy to import into Excel, databases, or math software for analysis.

Cons:

• Loss of Machine Readability: A simplified .TXT file can no longer control a CNC machine or be imported back into CAM software as a drill layer.
• Broken File Associations: Simply renaming an .NCD extension to .TXT stops PCB software from recognizing the file automatically.
• Metadata Loss: Stripping the file to raw coordinates removes Excellon headers, routing commands, and unit definitions.

Conversion Difficulties & Why Convert.Guru

The primary technical difficulty when you convert .NCD to .TXT is coordinate parsing. To save file space, Excellon .NCD files typically omit decimal points. A coordinate written as X01500 could mean 1.5 inches, 0.15 inches, or 15.0 millimeters, depending on the unit settings and zero-suppression rules (leading or trailing zeros) defined in the file header.

Naive conversion tools or manual copy-pasting often misinterpret these values, resulting in massive scaling errors. Convert.Guru handles this conversion accurately by reading the Excellon header, applying the correct zero-suppression and unit rules, and calculating the exact decimal values. It then outputs a cleanly formatted .TXT file, ensuring that the human-readable coordinates match the original physical design perfectly.

NCD vs. TXT: What is the better choice?

Which format should you choose?

You should keep your files as .NCD if you are sending them to a PCB manufacturer, importing them into CAM software, or operating a CNC drill. The .NCD format contains the exact syntax required for these tasks.

You should choose .TXT if you need to share drill coordinates with non-engineers, include hole locations in a report, or import the data into a spreadsheet. Avoid converting to .TXT if you plan to modify the coordinates and send them back to manufacturing, as rebuilding the strict Excellon syntax from a plain text file is highly error-prone.

Conclusion

Converting .NCD to .TXT makes sense when you need to extract PCB drill coordinates for documentation, analysis, or sharing outside of specialized engineering environments. The biggest limitation to watch for is the loss of CNC machine compatibility; a parsed text file cannot be used for actual manufacturing. For users who need to translate complex Excellon formatting and implicit decimals into accurate, readable data, Convert.Guru provides a reliable and technically precise solution to convert .NCD to .TXT without scaling errors.