Errata

Here you can find comprehensive information about errata that affect our data releases, including crawl data, and web graphs. If you have any problems to report please Contact Us.

Erroneous title field in WAT records

Originally reported by 
Robert Waksmunski
.

The title field in WAT record is extracted from last but not first <title> element in an HTML page

Earliest crawl:
 
CC-MAIN-2013-20
 
Latest crawl:
 
CC-MAIN-2024-33
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Missing fetch_status fields

Originally reported by 
"NL" via Discord
.

In our columnar index for this crawl, the `content_mime_type` is missing and `fetch_status` is always -1. In the cdx index (columnar: `content_mime_type`), fields "mime" and "status" are missing.

Earliest crawl:
 
CC-MAIN-2015-06
 
Latest crawl:
 
CC-MAIN-2015-11
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Redundant extra line in response records

Originally reported by 
Greg Lindahl
.

The WARC files of the August 2018 crawl contain a redundant empty line between the HTTP headers and the payload of WARC response records.

Earliest crawl:
 
CC-MAIN-2018-34
 
Latest crawl:
 
CC-MAIN-2018-34
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Incorrect fetch_time metadata

Originally reported by 
.

In crawls CC-MAIN-2016-36 to CC-MAIN-2016-50, the fetch_time metadata for robots.txt is incorrect.

Earliest crawl:
 
CC-MAIN-2016-36
 
Latest crawl:
 
CC-MAIN-2016-50
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Charset Detection Bug in WET Records

Originally reported by 
Javier de la Rosa
.

The charset detection required to properly transform non-UTF-8 HTML pages in WARC files into WET records didn't work before November 2016 (CC-MAIN-2016-50) due to a bug in IIPC Web Archive Commons.

Earliest crawl:
 
CC-MAIN-2008-2009
 
Latest crawl:
 
CC-MAIN-2016-44
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ARC Format (Legacy) Crawls

Originally reported by 
.

Our early crawls were archived using the ARC (Archive) format, not the WARC (Web ARChive) format.

Earliest crawl:
 
CC-MAIN-2008-2009
 
Latest crawl:
 
CC-MAIN-2012
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Missing Language Classification

Originally reported by 
.

Starting with crawl CC-MAIN-2018-39 we added a language classification field (‘content-languages’) to the columnar indexes, WAT files, and WARC metadata for all subsequent crawls.

Earliest crawl:
 
CC-MAIN-2008-2009
 
Latest crawl:
 
CC-MAIN-2018-34
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Some 2–Level CCTLDs Excluded

Originally reported by 
.

A bad configuration was checked into our exclusion list on Sep 22, 2022 and was fixed on Oct 27, 2023. The configuration blocked a number of 2–level domains, meaning they were not included in certain crawls.

Earliest crawl:
 
CC-MAIN-2022-40
 
Latest crawl:
 
CC-MAIN-2023-40
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