The crawl archive for December 2018 is now available! It contains 3.1 billion web pages or 250 TiB of uncompressed content, crawled between December 9th and 19th.
The December crawl contains page captures of 735 million URLs not contained in any crawl archive before. New URLs stem from:
- extracting and sampling URLs from sitemaps, RSS and Atom feeds if provided by hosts visited in prior crawls. Hosts are selected from the highest-ranking 60 million domains of the Aug/Sep/Oct 2018 webgraph data set
- a breadth-first side crawl within a maximum of 6 links (“hops”) away from the home pages of the top 50 million domains of the webgraph dataset
- a random sample of outlinks taken from WAT files of the November crawl
- 30 million external links sampled from Wikipedia data dumps
Archive Location and Download
The December crawl archive is located in the commoncrawl bucket at crawl-data/CC-MAIN-2018-51/.
To assist with exploring and using the dataset, we provide gzipped files which list all segments, WARC, WAT and WET files. By simply adding either s3://commoncrawl/ or https://data.commoncrawl.org/ to each line, you end up with the S3 and HTTP paths respectively.
The Common Crawl URL Index for this crawl is available at: https://index.commoncrawl.org/CC-MAIN-2018-51/. Also the columnar index has been updated to contain this crawl.
Please donate to Common Crawl if you appreciate our free datasets! We’re also seeking corporate sponsors to partner with Common Crawl for our non-profit work in open data. Please contact info@commoncrawl.org for sponsorship information.
Erratum:
No truncation indicator in WARC records
Due to an issue with our crawler, not all truncations were indicated correctly. A workaround to detect length truncation is to be suspicious if the length of the content is exactly 1048576 bytes. Truncations for time or network do not have such a workaround. In the WARC files this indicator is called "WARC-Truncated".
Erratum:
Missing content_truncated flag in URL indexes
The flag in our URL indexes (CDX and columnar) that indicates whether or not a WARC record payload was truncated was added in CC-MAIN-2019-47. This indicator is missing in our indexes for all previous crawl releases. In the CDX index this is referred to as "truncated", and the columnar index refers to this as "content_truncated".
For more information please refer to the blog post announcing the November 2019 crawl. The reason for the truncation is given only for truncated records following the WARC header field "WARC-Truncated".
Erratum:
SURT URLs do not properly encode non-UTF-8 percent-encoded characters
When constructing SURT (Sort-friendly URI Reordering Transform) URLs, percent-encoded characters that are not valid UTF-8 sequences were not being correctly handled. This could lead to inconsistencies in URL normalization and sorting, potentially causing incorrect deduplication or retrieval issues in datasets that rely on SURT-based indexing. This was addressed in commoncrawl/nutch@6b2d9ea.
Erratum:
WAT data: repeated WARC and HTTP headers are not preserved
Repeated HTTP and WARC headers were not represented in the JSON data in WAT files. When a header was repeated adding a further value of that header, only the last value was stored and other values were lost. This issues was fixed with CC-MAIN-2024-51, see ia-web-commons#18. All WAT files from CC-MAIN-2013-20 until CC-MAIN-2024-46 are affected.
Erratum:
WARC revisit metadata records
The revisit records in the Common Crawl WARC archives in all crawls from CC-MAIN-2018-34 to CC-MAIN-2024-46 (since Aug 2018) lack the metadata record which is attached to all response records. Fixed with CC-MAIN-2024-51, see commoncrawl/nutch#33. Note: before CC-MAIN-2018-34, WARC revisit records were not stored at all.
Erratum:
Erroneous title field in WAT records
The "Title" extracted in WAT records to the JSON path `Envelope > Payload-Metadata > HTTP-Response-Metadata > HTML-Metadata > Head > Title` is not the content included in the <title> element in the HTML header (<head> element) if the page contains further <title> elements in the page body. The content of the last <title> element is written to the WAT "Title". This bug was observed if the HTML page includes embedded SVG graphics.
The issue was reported by the user Robert Waksmunski:
- https://groups.google.com/g/common-crawl/c/ZrPFdY3pPA4/m/s5D_8wCJAAAJ
- WAT extractor: Document title bug ia-web-commons#36
...and was fixed for CC-MAIN-2024-42 by commoncrawl/ia-web-commons#37.
This erratum affects all crawls from CC-MAIN-2013-20 until CC-MAIN-2024-38.
Erratum:
Incorrect fetch_time metadata
In crawls CC-MAIN-2016-36 to CC-MAIN-2016-50, and CC-MAIN-2018-34 to CC-MAIN-2019-47 the fetch_time metadata for robots.txt might be incorrect. The correct times can be found in collinfo.json. See the related issue (commoncrawl/nutch#14) for more information.
.svg)
