An edit summary is an explanation of the changes made to a given page in an edit. Although not required, editors are encouraged to write accurate and detailed summaries (for more information, see Help:Edit summary on Wikipedia).
The edit summary box can hold one line of 200 characters. If you attempt to type or paste more, only the first 200 characters will be displayed - the rest will be disregarded. Also, for example attempting to add 10 new characters (at the end or in between) to a summary already containing 195 characters will result in the first 5 new characters being inserted and the second 5 being disregarded.
The "Show preview" button also provides a preview of the edit summary to facilitate checking links.
Always fill in the summary field. This is considered an important guideline. Even a short summary is better than no summary. An edit summary is even more important if you delete any text; otherwise, people may question your motives for the edit. Also, mentioning one change but not another one can be misleading to someone who finds the other one more important; add "and misc." to cover the other change(s).
Accurate summaries help people decide whether it is worthwhile for them to check a change. We've found that summaries often pique the interest of contributors with expertise in the area. This may not be as necessary for "minor changes," but "fixed spelling" would be nice even then.
In the case of a small addition to an article, it is highly recommended to copy the full text of this addition to the summary field, giving a maximum of information with a minimum of effort. Put ft in front, as an abbreviation of "full text" (see the Abbreviations section for other abbreviations). This way, readers of the summary will be unlikely to check the page itself as they already know the extent of the edit. These kinds of edits allow users to check Recent changes, Page history and User contributions (see below) very efficiently - this also reduces the load on the servers.
If the addition is more than 200 characters, so it does not fit fully in the edit summary box, you should write a short summary of the changes you have introduced into the article. For an addition of, say, 400 characters you can also save time by simply copying that into the summary field. The excess will fall off, and the first 200 characters will usually be acceptable as a crude "summary."
Unfortunately you can copy only one line of text from the edit box into the edit summary box. The contents of further lines can be pasted at the end of the line. Thus, for example, a bulleted "see also" list is cumbersome to put in the edit summary box. One possible workaround for a new list is putting the list on one line, separated by the asterisks for the bullets, copying it to the edit summary box, and then, in the main edit box, putting the new lines before the asterisks.
In addition to a summary of the change itself, the summary field may also contain an explanation of the change; note that if the reason for an edit is not clear, it is more likely to be reverted, especially in the case that some text is deleted. To give a longer explanation, use the Talk page and put in the edit summary "see Talk."
After saving the page, the summary can not be edited--another reason to avoid spelling errors.
In the case of important omissions or errors in the edit summary, you can make a dummy edit just to put the correction in the edit summary.
The edit summary appears in black italics in the following places:
- Page history - list of changes to the page you edited
- User contributions - list of all your edits
- Watchlist - list of recent changes to watched pages (logged-in users only)
- diff page - shows the difference between two edits
- Recent changes - list of all recent edits
- List of new pages: shows the edit summary of the creation.
* Use the enhanced watchlist to see all recent changes in the watched pages, not just the last change in each page.
See Edit summary legend for a list of commonly used abbreviations in edit summaries.
When uploading an image one can supply an upload summary. This serves multiple purposes:
- as second part of the automatically created edit summary of the upload log (the first part giving the file name)
- as text in the entry of the image history
- in the case that the file name of the image is new:
The capacity of the upload summary is one line of 250 characters; in the upload log the last part may fall off, because this can contain 255 characters, including "uploaded filename."
Note that there is no preview function to check the code for the links, template calls and category tags, but of course, if needed one can edit the image page after uploading, to correct errors and also to extend the text.
When applying the section editing feature the section title is automatically inserted as initial version or first part of the edit summary. Put more details after this text. In the case that you provide a long summary yourself you can delete the section title in order to stay within the limit of 200 characters. The automatic text appears by default in gray, with the manually typed text being black. If you create a new section before or after an existing section by clicking a section "edit" link, please delete the automatic edit summary to avoid confusion.
For edits made before May 2004, the automatic part of the summary is surrounded by "=" signs.