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The rollback feature is a part of the MediaWiki software. It is a way to quickly undo vandalism made by the last user to change the page. It is given to administrators as part of their work.

Rollback can also be given to people who are not administrators. Such people are referred to as rollbackers. You may ask for rollback at Wikipedia:Requests for rollback or on an administrator's talk page.

Rollback is available to all 22 Wikipedia administrators, and there are 413 users with the rollbacker permission locally. In total, 435 editors have rollback rights. Apart from them, global rollbackers and stewards also have access to rollback.

Using rollback

Rollback is a tool normally only used to reverse obvious vandalism. This is because it does not let you leave a change summary. Instead, the summary reads, "Reverted changes by X to last version by Y". It is done at once and does not need you to make sure you are doing it, which is different from the undo feature.

Rollback may also be used to rollback changes by yourself. Unhelpful changes made in your userspace may also be rolled back. If you are not sure whether to use this tool on a single change, please use the undo feature. If you make an obvious mistake, or you need to revert your changes quickly, using rollback on yourself is also allowed. Generally, a person with rollback may also use it to revert their own edits in mainspace as long as those edits are a mistake and also not likely to cause a dispute.

When not to use rollback

Rollback must not be used to remove good-faith changes by other users, registered or not. If the tool is repeatedly used incorrectly, it will be quickly removed by an administrator.

How it works

Rollback is the fastest way to undo a change, and does not put pressure on the servers. If the vandal made one change, the rollback button will change back to the older change just before the vandal. The rollback button will undo every change by the last user, so if the vandal changed it 6 times in a row, all six changes will be removed. If another user changed after the vandal, the rollback feature will change back to that user's changes, and will not undo all the changes by that user.

The feature leaves an automatic change summary, for example:

m Reverted edits by Example (talk) to last version by Example2

The software automatically marks the change as "small" or "minor", hence the m.

Getting rollback

You may ask for rollback at requests for rollback. You may also use the administrators noticeboard, or ask on an administrator's talk page. Please note these rules:

• You should meet the requirements for autoconfirmed user (registered for 4 days with 10 edits) when requesting. User rights cannot be given to IP editors.
• You should have made a lot of changes, with experience in anti-vandalism work. If you have rollback elsewhere, or admin rights elsewhere, the threshold for meeting this requirement is lower. So if you are already a rollbacker or admin on another Wikimedia Foundation project, please mention it in your request and it will be taken into consideration.
• If you have been blocked recently, it is unlikely that you will be given rollback.
• If you have vandalized before, you may not be given this tool for a long time. Administrators can choose if they want to give it to you, but only if you have shown a clear change in your behaviour.

Testing rollback

Testing the tool can be done at Wikipedia:Rollback feature/Testing ground. Please do not test on other people's changes.

Custom edit summaries

The rollback tool has an edit summary that is given by default. There are tools to let you change summaries. Some examples are:

• User:Synergy/rollback.js
• User:Synergy/rollback2.js
• User:Tholly/Rollback.js?
• User:MC10/Rollback summary.js

Reverting all rollbackable changes made by a single user

There are scripts that let you rollback every rollbackable change by a user. One example is en:User:John254/mass rollback.js.