FASTA Sequence File

David J. Lipman and William R. Pearson created the FASTA format and released it in 1985. Many DNA apps have adopted support for the format because of its simplicity, making it one of the most common formats for transferring sequences between applications.

The FASTA format

FASTA files often start with a header line that may contain comments or other information. The rest of the file contains sequence data. Each sequence starts with a > character followed by the name of the sequence. The rest of the line describes the sequence, and the remaining lines contain the sequence itself.

NOTE: Files saved in the FASTA format may use various file extensions besides .fasta , such as .fas ( .FAS files) and .fa ( .FA files).

You can open a FASTA file with several DNA applications, such as GSL Biotech SnapGene (multiplatform), Genome Compiler (multiplatform), and Heracle BioSoft DNA Baser (Windows). For example, you can open a FASTA file with SnapGene by selecting File → Open Files... .

Opening a FASTA file with a text editor

You can also open a FASTA file with a text editor, such as Microsoft Notepad (Windows) or Apple TextEdit (Mac). You can also open a FASTA file with source code editors. However, opening the FASTA file with a text editor or source editor will not natively display the sequence in the FASTA file like a DNA app.

When opened in a text editor or source code editor, you can view the sequence in the FASTA file and modify its properties. However, if you incorrectly edit the sequence, you may corrupt it.

Various applications, such as GSL Biotech SnapGene and Heracle BioSoft DNA Baser, can convert FASTA files to other formats.

For example, SnapGene can convert FASTA files to the following formats:

Programs that open FASTA files

Updated: October 13, 2022