Welcome to GC-AutoFit

Analyze GC-MS spectra with built-in or custom libraries

GC-AutoFit identifies and quantifies metabolites from GC-MS spectra using retention indices, EI-MS spectra, and the selected reference library. Query spectra should be prepared according to the GC-AutoFit collection instructions for best performance.

This workflow accepts .CDF, .mzML, and .mzXML spectra packed into a single ZIP file. Alkane standards are required, blank spectra are optional, and up to 30 sample spectra are recommended per submission.

Step 1

Choose a library

Select a built-in biofluid library or upload your own RI and calibration libraries.

Input:Urine, Serum, or Custom Library
Step 2

Upload spectra ZIP

Include alkane standards, an optional blank, and one or more sample spectra.

Accepted:.CDF, .mzML, .mzXML in one .zip
Step 3

Review and submit

Confirm the internal standard and MF score cutoff, then launch the analysis.

Output:Identified compounds and quantification results

Submit Your GC-MS Spectra for Fast, Automated Profiling and Quantification


Select a biofluid library

For each biofluid, GC-AutoFit can run against a pre-generated reference library or your own custom library files. The built-in libraries include a broad set of compounds commonly found in each biofluid, while custom libraries can be tailored to specific subsets of compounds relevant to your study.

Edit Subset
Edit Subset

Upload Package

Upload one ZIP file containing alkane standards, an optional blank, and at least one sample spectrum. All files must be at the top level of the ZIP and follow the naming conventions described in the instructions. Up to 30 sample spectra are recommended per submission.

Required spectra:

  • One alkane standards spectrum alk-std.CDF, Alkstd.mzML, alkstd.mzXML
  • Optional blank spectrum Blank.CDF, Blk.mzXML
  • One or more sample spectra with any naming convention, but in .CDF, .mzML, or .mzXML format

For more information on file naming conventions and formatting requirements, see the instructions page.

  quantification_example_urine_samples.zip example Urine dataset collected and prepared by our team
  quantification_example_serum_samples.zip example Serum dataset collected and prepared by our team

Drag and drop your ZIP package here

or click to browse for the upload file

No file selected

File formats required in the zipped file:

Spectrum files:

  • Must include alkane standards and at least one sample spectrum
  • May include an optional blank spectrum
  • .CDF, .mzML, .mzXML

Package all files into a single .zip with files stored at the first level.


More internal standard options coming soon! Contact us if you have a specific request.

An integer between 0 and 999. A range between 400 and 600 is usually appropriate.