Wikipedia:Preparing images for upload

This page documents an English Wikipedia editing guideline. It is a generally accepted standard that editors should attempt to follow, though occasional exceptions may apply. Any substantive edit to this page should reflect consensus. When in doubt, discuss first on the talk page.

Shortcut WP:PIFU

When uploading image files to Wikipedia or, preferably, to the Wikimedia Commons, it is important to use the right file format for the content. Don't try to save disk space on the images server by giving up useful information.

Keep the source:

• If the image was generated from data (e.g. a graph in Microsoft Excel), the data and file (e.g. spreadsheet) should be included so new data can be added to the graph, and/or the source of the data should be cited.
• If the image was generated from a script (e.g. in a computer algebra system), the code should be included so minor improvements like labels and color adjustments can be made.
• In any of the above cases, there should be a note saying what specific software is required to edit the image. Data formats and code that are compatible with free software should be preferred.

There are 4 basic choices for image file formats:

SVG for simple diagrams (especially those that need to be scaled).

JPEG for photographic images.

GIF for animated images.

PNG for everything else.

While some formats offer multiple compression systems, in general the format and the compression system are tied together.

Other image formats should be avoided in most cases:

BMP - Images are uncompressed, resulting in larger file sizes. Should usually be converted to PNG.

TIFF - Should usually be converted to PNG or JPEG as discussed above.