Editing Encyclopedia:Image use policy (section)

===Displayed image size===
{{Shortcut|WP:THUMBSIZE|WP:IMGSIZE|WP:IMAGESIZE}}
{{Further|Wikipedia:Manual of Style/Images#Size|Wikipedia:Manual of Style/Accessibility#Images}}
{{redirect|WP:IMAGESIZE|text=You may be looking for [[#Uploaded image size|Uploaded image size]], another section on this page}}
Images adjacent to text should generally carry a [[Wikipedia:Manual of Style/Captions|caption]] and use the "<code>[[Wikipedia:Picture tutorial#thumb|thumb]]</code>" (thumbnail) option, which displays the image as follows:
*A1. The default width is 220px ([[pixel]]s), unless the user changes the relevant setting in preferences (before any scaling due to <code>upright</code>{{emdash}}see B below).
*A2. For a logged-in user, the width{{mdashb}}before any scaling due to <code>upright</code>{{mdashb}}is set in the [[Help:Preferences#Files|user preferences]].
*B. If the <code>[[Wikipedia:Picture tutorial#upright|upright]]</code> parameter is present, then the initial width determined by A1 or A2 is multiplied by the ''upright'' scaling factor.  This allows article editors to adjust the user's "base" image-size preference, according to the characteristics of a particular image. For example:
**<code>|thumb|upright=1.4</code> might be used for an image with fine detail, so that it will be rendered "40% larger than the user generally specified".
**<code>|thumb|upright=0.75</code> might be used for an image with little detail, which can be adequately displayed "25% smaller than the user generally specified".

Notes:
*<code>|thumb</code> (with <code>upright</code> completely absent) multiplies the width by 1.0 (i.e. changes nothing)
*<code>|thumb|upright</code> (with <code>upright</code> present, but no multiplier given) multiplies the width by 0.75 by default
*{{para|upright|''scaling_factor''}} can be used not only for thumbnails but for certain other images that serve much the same function as thumbnails but do not need frames around them or captions below them. In these cases add {{para||frameless}}.

See the {{section link|Wikipedia:Manual of Style/Images|Size}} for further guidance on expanded or reduced image sizes.
'''Except with very good reason, do not use''' <code>px</code> (e.g. <code>|thumb|300px</code>), '''which forces a fixed image width measured in pixels, disregarding the user's image size preference setting.''' In most cases {{nobr|1=<code>upright=''scaling_factor''</code>}} should be used, thereby respecting the user's base preference (which may have been selected for that user's particular devices). If <code>px</code> <em>is</em> used, the resulting image should usually be no more than 500 pixels tall and no more than 400 pixels wide, for comfortable display on the smallest devices "in common use" (though this may still cause viewing difficulties on some unusual displays). To convert a <code>px</code> value to <code>''scaling_factor''</code>, divide it by 220 and round the result as desired. For example, {{para||150px}} is roughly equivalent to {{para|upright|0.7}} (150 / 220 ≃ 0.6818).

====Infobox and lead images====
{{shortcut|WP:IMGSIZELEAD}}
Stand-alone lead images (not in an infobox) should  be no wider than <code>upright=1.35</code> (equivalent to 340px at the default preference selection of 250px after rounding up to multiples of four pixels)
also be no wider than <code>upright=1.35</code>.

The lead image in an [[WP:INFOBOX|infobox]] should not impinge on the default size of the infobox. Therefore, it should be no wider than <code>upright=0.9</code> (equivalent to 228px). Images in infoboxes are generated by many different means. The most common method used to implement <code>upright</code> is [[Module:InfoboxImage]] (see documentation there).  Alternatively, infoboxes can use standard [[Wikipedia:Extended image syntax|image syntax]] in the form of:
:<code><nowiki>[[File:Westminstpalace.jpg|frameless|center|upright=</nowiki>''scaling_factor''<nowiki>]]</nowiki></code>