Read Balzer Quadstar files

The software which is provided with the Balzer quadrupol mass spectrometer QMS200 (residual gas analyzer) has only limited possibilities to handle data. To analyze the spectra with statistical methods or to fit some curves, you have to export the sac files to a csv file in order to use them with other software. Yet, the ability of the software to export the data to a csv file is rather limited as you have to save every single measurement cycle individually.

The first time I ran into this problem, I tried to measure for a long period (several hours) and got a lot of cycles with analog scans. To export several 1000 cycles individually, I would still be clicking...


To overcome this problem, I wrote a small program. The information is directly from the specification of the SAC-files, which I got from Inficon. The program reads the file and returns the data to STDOUT.

Usage in linux command line

sac2dat OPTION filename.sac

following options:

-iread information of the measurement
-aread out all cycles
-s NRread cycle number NR


After requests by people from all over the world, I finished the mdc2dat program. As I left academia after my PhD I cannot produce new data files anymore (as I have no QMS anymore). So I can only check this program with old files I measured some years ago. Please feel free to test it with newer data and let me know if there are any issues.


sac2dat executable (linux)
sac2dat.exe (win32)
sac2dat.c source code
mdc2dat executable (linux)
mdc2dat.exe (win32)
mdc2dat.c source code


Thank you for writing the program sac2dat. In our lab we are still using quadstar on a daily basis and your code makes life a little bit easier for us.

Matthijs van Spronsen, Leiden University, 2012

Allerdings ist es schon etwas umständlich, gleich mehrere MS-Spektren (cycles) in einfache Textfiles zu exportieren - bis ich Ihr Konvertierungsprogramm im Netz gefunden habe!
Das Programm SAC2DAT funktioniert wirklich wunderbar!

Robert Jäger, TU Darmstadt, GSI, 2012

It was great to find you've developed the SAC2DAT tool to export Balzers (and Inficon) SAC files to text!

Arnoud Onnink, University Twente, NL 2019