Skip to Content

What file formats should I use?

Before you digitize your physical items, you will need to take some time to determine what digital file format you will safe your output in.  Many institutions save each item in both a preservation and access file format.  The access format is often smaller in size to make it quicker to download or send to the user, and it can be in file formats that are less sustainable.  Preservation file formats should always be long-lasting and are often much bigger than access formats.  The idea is to save the item in a format that can be used far in the future to create new access versions or to migrate to newer and more sustainable file formats as technology changes.



  • Association for Library Collections and Technical Services' Minimum Digitization Capture Resolutions

"This document was created as a guideline for libraries digitizing content with the objective of producing a sustainable product that will not need to be re-digitized. Institutions can feel secure that if an item has been digitized at or above these specifications, they can depend on it to continue to be viable in the future. In some cases, institutions may want to request a digital copy to preserve themselves, further safeguarding materials by preserving them in multiple locations."

  • Florida Center for Library Automation.  "Preservation."  Chapter 2 in Digital Oral History Workflow, 2008.

  • Office for Information Systems - Harvard University Library. “File Formats & Guidelines.”


  • Arms, Carolyn & Karl Fleischhauer. Sustainability of Digital Formats: Planning for the Library of Congress.

The Digital Formats Web site provides information about digital content formats. The analyses and resources presented here will increase and be updated over time.

  • Brown, Adrian. “Selecting File Formats for Long-Term Preservation.” Digital Preservation Guidance Note 1. London: The National Archives, August 2008.

This document is one of a series of guidance notes produced by The National Archives, giving general advice on issues relating to the preservation and management of electronic records. It is intended for use by anyone involved in the creation of electronic records that may need to be preserved over the long-term, as well as by those responsible for preservation.This guidance note provides information for the creators and managers of electronic records about file format selection.

  • CENDI Digital Preservation Task Group. Formats for Digital Preservation: A Review of Alternatives and Issues.

"Many digital file formats can be considered for preservation. CENDI agencies, however, are most
concerned with formats that best preserve text documents such as technical reports and journal
articles. For this reason the report focuses on four major formats in the context of document
preservation – TIFF, PDF, PDF/A, and XML."\

  • Rog, Judith and Carolina van Wijk.  "Evaluating File Formats for Long-term Preservation.”  National Library of the Netherlands, 2007. 

Describes the quantifiable file format risk assessment method, which can be used to define digital preservation strategies for specific file formats, and intends to inspire other cultural heritage institutions to define their own quantifiable file format evaluation method.

  • Rusbridge, Chris and Kevin Ashley.  Responses to the Technology Watch Report on File Formats   . . . or data streams?  

Ed Pinsent wrote a blog in response to the Malcolm Todd report.  Rusbridge responded on December 7, 2009, and raised questions about lossy migration; Ashley responded on December 8, 2009, and added some further information about the seminar that led to the Technology Watch Report.

  • Todd, Malcolm.  "Technology Watch Report: File Formats for Preservation."  Digital Preservation Coalition, October 2009.  

Considers various criteria for file formats: adoption, technological dependencies, disclosure, transparency, metadata support, reusability/interoperability, robustness/complexity, stability, intellectual property/digital rights production, and the ability of formats to convey content information.


about seo | page