Commons:Maximum file size

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COM:MAXSIZE

The maximum file size on Commons is set to 4 GiB (4,294,967,296 bytes) for users who enable the "Chunked uploads" setting in their user preferences.[1][2] Otherwise the limit is 100 MiB (104,857,600 bytes)[3] because of technical issues in the uploading.[4][5] It is also possible to upload files using server-side upload.

This means that it is not possible to upload a file larger than the maximum file size without first breaking it into smaller parts, and uploading those parts as separate files. The template {{Split file}} can be used to link the parts of files split in this way.

Please note that every effort should be made to keep files under the file size limit without splitting them. There are various means to do this, including changing file formats, removing parts of a file not really needed, and downsampling resolution, increasing compression levels, etc. Only where these measures aren't enough (because further loss of detail would reduce quality too much) should files be split.

In particular, tiff images are often very large, but can have their file size reduced by enabling compression. As long as the compression method is lossless (Such as "deflate" or "LZW"), the file size reduction does not affect image quality (But beware of obscure compression methods which can cause data loss, or make the file incompatible with some software).

On the other hand, there is no limit to the total size of uploads by an individual account. However, if you plan batch uploads amounting to several TB, it may be wise to warn the sysadmins.

Maximum size for thumbnails[edit]

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COM:MAXTHUMB

In addition to the general size restriction, for several filetypes (GIF) the software only produces thumbnails and previews on the main file description page below a certain size limit − currently, 50 megapixels.[6][7] However, large GIF animations can be currently affected by another restriction, by a (memory limit) bug upward ~23 MP.[8] For files where the software does not provide thumbnails because of this limitation, a thumbnail version (either a full-sized JPEG or a smaller PNG) should be uploaded for thumbnail/preview purposes, and linked with the main file. The templates {{Archival version}} and {{Compressed version}} are available for this.

SVG files are currently subject to a 10 MB limit[9]

PNG files now have a much larger limit, of very approximately 2,500 megapixels (since August 2013).

An unrelated reason thumbnails may fail to display (example) is for very long filenames – so long that they approach the 255-byte limit of filename length (which for some cases with non-ASCII characters may be much less than 255 characters, due to UTF-8). Its impossible to upload a file that has a name this large, but it is possible to move a file to such a name.[10]

Technical notes[edit]

  1. Originally 500 MiB, increased to 1 GiB in November 2013, increased to 2 GiB in Feb 2016, increased to 4 GiB in April 2016
  2. This might not be working for PDF files at the moment, due to phab:T94562
  3. It has been 20 MB for a while and was raised to 100 in November 2008.[1]
  4. Village pump (2011-11)
  5. Wikitech-l (2010-07)
  6. The limit was 12.5 megapixels, or about 3500 x 3500, before Bugzilla: 41125 raised the limit in October 2012. The general limitation is under Bugzilla: 9497.
  7. This is because these filetypes can only be thumbnailed by MediaWiki's ImageMagick library by first decompressing the entire image in RAM, which can cause severe server loads. https://lists.wikimedia.org/pipermail/wikitech-l/2005-October/019681.html
  8. Bugzilla: 61711 – bigger GIF animations (> ~23 MP) may be affected by a out of memory limitation, see :Category:Animated GIF files affected by MediaWiki restrictions for more.
  9. phab:T111815
  10. Bugzilla30202

Help[edit]