WARC

archive · also known as ISO 28500-2009, Web ARChive file format

The WARC (Web ARChive) file format offers a convention for concatenating multiple resource records (data objects), each consisting of a set of simple text headers and an arbitrary data block into one long file. The WARC format is an extension of the ARC file format (ARC) that has traditionally been used to store "web crawls" as sequences of content blocks harvested from the World Wide Web (…) Besides the primary content recorded in ARCs, the extended WARC format accommodates related secondary content, such as assigned metadata, abbreviated duplicate detection events, later-date transformations, and segmentation of large resources”. WARC format has been written by the members of the IIPC (http://www.netpreserve.org/) grouped within the ISO/TC46/SC4/WG12.

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• ArchiveBoxOpen sourcewrites · MIT License
• ConiferOpen sourcereads and writes · Apache Software License 2.0
• HeritrixOpen sourcereads and writes · Apache Software License 2.0
• NutchOpen sourcereads and writes · Apache License
• StormCrawlerOpen sourcereads and writes · Apache License / Apache Software License 2.0
• warctoolsOpen sourcereads and writes · MIT License
• InterPlanetary WaybackOpen sourcereads · MIT License
• JHOVEOpen sourcereads · GNU Lesser General Public License
• Webrecorder PlayerOpen sourcereads · Apache Software License 2.0
• ArchiveWeb.pagereads and writes
• Browsertrixwrites
• Wgetwrites

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Versions and variants (2)

• WARC 1.0Unknown
• WARC 1.1Writable

Sources

• File Formats Wiki
• PRONOM fmt/289
• Wikidata Q7978505

From Just Solve the File Format Problem (File Formats Wiki), PRONOM, Wikidata. Updated 2026-10-24.

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