Opening ALN Files

The ALN file type is primarily associated with ClustalW.

ALN	File extension: ALN
	File type:	text file

What is an ALN file?

ALN files mostly belong to ClustalW.

ALN files are used for multiple sequence alignments in bioinformatics. They store aligned DNA, RNA, or protein sequences as plain text. These files are generated by software such as ClustalW and Clustal Omega.
Some ALN files also contain data for structural analysis, for example, in plane frame analysis using LINPRO.
Key points provided by FilExt.com include:

They are plain text files designed for sequence comparison.

They are best viewed with specialized alignment tools.

They are integrated with services like EBI JDispatcher for further analysis.

FilExt.com note: To open an ALN file, use bioinformatics applications such as ClustalW or Clustal Omega. Although you can open them in a basic text editor, the alignment display is clearer with dedicated software.

How can I open an ALN file?

You need a suitable software like ClustalW to open an ALN file. Without proper software you will receive a Windows message "How do you want to open this file?" or "Windows cannot open this file" or a similar Mac/iPhone/Android alert. If you cannot open your ALN file correctly, try to right-click or long-press the file. Then click "Open with" and choose an application. You can also display a ALN file directly in the browser:. Just drag the file onto this browser window and drop it.

Online ALN Text Viewer

Choose your .aln file to view

or drag and drop it here

Online File Viewer

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How to extract texts from ALN files or capture a screenshot to PDF, JPG, DOCX, TXT, ...

You can extract texts from ALN file or capture a preview screenshot using our online ALN file viewer:

To do this, click the button "Choose your .aln file to view" on this page.
After your file is opened in browser,
click "Save as..." in the menu.
Then choose the file format (e.g. JPG, PDF, DOCX, TXT, ...) you want.
Your file will be converted and downloaded.

Programs that open and convert ALN files:

ClustalW
See the previous paragraphs to learn more about the main application. ALN files are often referred to as ClustalW data files because this type of file is primarily created or used by this software.
Grlib Saoimage File
LexNavigator (Database Update) by UltraTech Group
This file updates the associated database files.

ALN file format:

Each file has a definite file format, that is, how the stored data is arranged in the file. The file format can be deduced from the file extension and the signature. File extension, signature and file format must match; otherwise errors will occur when the file is opened. If there are problems opening a file, you must first determine the file format used. Our analysis of the ALN files produces the following result:

The ALN extension is quite commonly used. The file itself is used by a few programs, each with its own file format. The file formats most commonly found in ALN files are:

60% of all ALN files belong to Clustal Alignment format. These files contain text and words, not binary data. A typical file size is 4 KB. It is a modern file type. Several words can almost always be found in the files, e.g. CLUSTAL 2.1 multiple sequence alignment. Examples of file names are clustalw.aln. Such files are related to alignment, enst, results, guide, mafft, seed, align and human.
7% of all ALN files start with the magic bytes >lcl|, which are always the first bytes of this file format. The content consists of readable text data, which can be read using a text editor. The file size is in the range of 1 KB to 330 KB. Several words can almost always be found in the files, e.g. Query and >lcl!consensus. These files can be linked to sequences, other, query and maize.

All other ALN files (33%) have no uniform format, often, for example, ref and LINPRO. These files sometimes refer to core, gene, sequence, fasttree, ortholog, phylip, clean, fasta or morga. If you want to find out which format your ALN file belongs to, just click on the button "Choose your .aln file to view".

Technical Data for ALN File Extension

File classification:

Data

Related files:

fasta, phy, nexus, msa, clustal, seq, emb, dnd, praln, clustal_num, fasta_aln, clw, ph, phy, pir, align, anl, fa, zip, fas, msf, txt, phb, gz, h5, rtf

Mime type:

text/plain

The following listing is compiled from the database produced by the 'Associate This!' program, selected data from the main FILExt database and file extension information submitted by users.

ProgramID: ALNfile
EXEFile: %ProgramFiles%\LexNavigator\LexUpdate.exe %1

an aln text file is a special file format and should only be edited and saved with the appropriate software.

How to solve problems with ALN files

Associate the ALN file extension with the correct application.
Update your software that should actually open text files. Because only the current version supports the latest ALN file format. Search, therefore, e.g. on the manufacturer website after an available ClustalW update.
To make sure that your ALN file is not corrupted or virus-infected, get the file again and scan it with Google's virustotal.com.
Click here to open your .ALN file online - secure, fast, and no downloads needed.