Introduction
This document identifies file formats that have been recognized by the archival community as sustainable and well-suited for long-term preservation. If possible, you should create or maintain files in these preservation-quality formats because they are one or more of the following:
- non-proprietary, so the format is not tied to one piece of software or the platform developed by a single company
- “open,” in that key characteristics and specifications of the format are well-known and documented so that anyone can use or implement the format
- widely-used so that the format will not soon become obsolete (as happened with formerly popular word processing formats like Word Perfect)
- recognized as a standard by groups like the ISO, ECMA International, and OASIS as well as the Library of Congress
By employing sustainable, preservation-quality formats, you (or your organization) greatly increase the likelihood that your content will remain accessible and fully functional into the foreseeable future.
Format Recommendations by Media Type
| Media Type | Recommended Formats |
|---|---|
| Office Documents and Text-Based Files | DOCX: MS Word Open XML Document (created in MS Office 2007 and 2010) |
| XLSX: MS Excel Open XML Document (created in MS Office 2007 and 2010) | |
| PPTX: MS PowerPoint Open XML Document (created in MS Office 2007 and 2010) | |
| ODT: OpenDocument Text Document (created in OpenOffice) | |
| ODS: OpenDocument Spreadsheet (created in OpenOffice) | |
| ODP: OpenDocument Presentation (created in OpenOffice) | |
| PDF/A: Portable Document Format (Archival) (more information) | |
| TXT: Plain Text File (ANSI or UTF-8 encoded) | |
| RTF: Rich Text Format File | |
| XML: Extensible Markup Language Data File | |
| CSV: Comma Separated Values File | |
| TSV: Tab Separated Values File | |
| Audio Files | WAV: Waveform Audio File Format (more information) |
| AIFF: Audio Interchange File Format | |
| MP3: Moving Picture Experts Group Layer 3 compression | |
| FLAC: Free Lossless Audio Codec File | |
| OGG: Ogg Vorbis Audio File | |
| Video Files | MPEG-1/2: Moving Picture Experts Group |
| AVI: Audio Video Interleave File (uncompressed) | |
| MOV: Quicktime Movie (uncompressed) | |
| MP4: Moving Picture Experts Group (with H.264 encoding) | |
| MJ2: Motion JPEG 2000 | |
| DV: Digital Video File (non-proprietary) | |
| Raster (or Bitmap) Image Files | TIFF: Tagged Image Format File |
| JPEG/JFIF: Joint Photographic Experts Group JPEG Interchange Format File (lossy compression) | |
| JPEG 2000: Joint Photographic Experts Group (lossless compression) | |
| GIF: Graphic Interchange Format | |
| PNG: Portable Network Graphic | |
| Vector Image Files | SVG: Scalable Vector Graphics File |
| Email Files | MBOX:Mailbox File |
| NOTE: A major limitation of ‘free’ Web-mail such as Gmail, Yahoo, or Hotmail is the inability to easily download or export messages to a different email client or your desktop. Using Mozilla Thunderbird, Outlook, MacMail, or similar clients may allow you to save local copies of messages and be platform-independent. | |
| Database Files | CSV: Comma Separated Values File |
| MySQL SQL: Structured Query Language file (MySQL is an open source relational database management system) |