The File Extensions Database

.MAF File Extension

  • Developer by: National Cancer Institute
  • Category: Data Files
  • Format: Text

What is an .MAF file?

.MAF is Mutation Annotation Format File

Text file created in the Mutation Annotation Format (MAF), a file format used to capture mutations in cells; saves cell and genome information using tab-delimited text; used in cancer studies for capturing somatic mutations and single-nucleotide polymorphism (SNPs).

The MAF format is maintained by the National Cancer Institute and the National Human Genome Research Institute (NHGRI) under a project named The Cancer Genome Atlas (TCGA). The format is primarily used by custom research analysis software applications. However, MAF files can be viewed with any text editor.

NOTE: The MAF format has undergone several revisions. Version 2.2 supports 32 different tab-delimited columns.

Programs that open Mutation Annotation Format File
Microsoft Notepad
Microsoft WordPad
File Type 2:

Microsoft Access Form

Developer by: Microsoft Category: Database Files

Form used in a Microsoft Access database.

Programs that open Microsoft Access Form
Microsoft Access 2016

How to solve problems with MAF files

  • Associate the MAF file extension with the correct application. On :
    Windows: Right click on any MAF file and then click "Open with" > "Choose another app". Now select another program and check the box "Always use this app to open *.MAF files". Mac: Right click (or Ctrl-click) the MAF file, then click "Open with" > "Other...". Then choose another program and check the "Always Open With" box. Linux: Right click on the file, and select "Open with" and choose another program. iPhone: Tap the file. If you do not see an app to open the file, then tap Share "Share" and choose an app. Alternatively, save the file. Then open the Files app Files app. There long-press on the file, then release your finger. You will see a black menu bar. Then tap "Share" and select an app. Android: Tap the Settings icon on your smartphone, then tap on the Apps section. There tap the Options icon in the top right-hand corner of the screen to change the default apps.
  • Update your software that should actually open .MAF is Mutation Annotation Format File. Because only the current version supports the latest MAF file format. Search, therefore, e.g. on the National Cancer Institute manufacturer website after an available .MAF is Mutation Annotation Format File update.
  • To make sure that your MAF file is not corrupted or virus-infected, get the file again and scan it with antivirus software.