Object Classes

All anomalous objects, entities, and phenomena requiring Special Containment Procedures are assigned an Object Class. An Object Class is a part of the standard SCP template and serves as a rough indicator for how difficult an object is to contain. In universe, Object Classes are for the purposes of identifying containment needs, research priority, budgeting, and other considerations. An SCP's Object Class is determined by a number of factors, but the most important factors are the difficulty and the purpose of its containment.

Primary Classes

These are the most common Object Classes used in SCP articles, and make up the bulk of the objects.


Safe-class SCPs are anomalies that are easily and safely contained. This is often due to the fact that the Foundation has researched the SCP well enough that containment does not require significant resources or that the anomalies require a specific and conscious activation or trigger. Classifying an SCP as Safe, however, does not mean that handling or activating it does not pose a threat.

For a complete list of Safe-class articles on the site, click Safe.


Euclid-class SCPs are anomalies that require more resources to contain completely or where containment isn't always reliable. Usually this is because the SCP is insufficiently understood or inherently unpredictable. Euclid is the Object Class with the greatest scope, and it's usually a safe bet that an SCP will be this class if it doesn't easily fall into any of the other standard Object Classes.

As a note, any SCP that's autonomous, sentient and/or sapient is generally classified as Euclid, due to the inherent unpredictability of an object that can act or think on its own.

For a complete list of Euclid-class articles on the site, click Euclid.


Keter-class SCPs are anomalies that are exceedingly difficult to contain consistently or reliably, with containment procedures often being extensive and complex. The Foundation often can't contain these SCPs well due to not having a solid understanding of the anomaly, or lacking the technology to properly contain or counter it. A Keter SCP does not mean the SCP is dangerous, just that it is simply very difficult or costly to contain.

For a complete list of Keter-class articles on the site, click Keter.


Thaumiel-class SCPs are anomalies that the Foundation specifically uses to contain other SCPs. Even the mere existence of Thaumiel-class objects is classified at the highest levels of the Foundation and their locations, functions, and current status are known to few Foundation personnel outside of the O5 Council.

For a complete list of Thaumiel-class articles on the site, click Thaumiel.

++ Neutralized

Neutralized SCPs are anomalies that are no longer anomalous, either through having been intentionally or accidentally destroyed, or disabled.

For a complete list of Neutralized-class articles on the site, click Neutralized.

Non-Standard Object Classes

The following Object Classes are sub-classes that supplement the object's primary (or former) classification.


Explained SCPs are commonly articles about anomalies that are completely and fully understood to the point where their effects are now explainable by mainstream science or phenomena that have been debunked or falsely mistaken as an anomaly.

For a complete list of Explained-class articles on the site, click Explained.

Esoteric/Narrative Classes

Esoteric Object Classes, also occasionally referred to as Narrative classes, are Object classes that do not fall into any of the above sections. They are generally only used once and are created to further the narrative in a particular SCP. It is highly recommended that SCPs use one of the standard Object Classes listed here. While some authors choose to introduce exceptions to these rules, they are only very rarely done and need to justify their existence and placement. Many site members will downvote for non-standard Object Classes if used without merit.

For a complete list of articles with Esoteric classes on the site, click Esoteric/narrative.


Decommissioned SCPs are an Object Class that was used by senior staff in the past to not only delete unwanted articles but place them in a sort of "Wall of Shame" to serve as examples of what not to do. This Object Class is not used anymore.

Decommissioning articles is not done anymore, partly because such heavy-handed edits by SCP staff are no longer allowed and partly because decommissioning ended up backfiring. See the History of the Universe Hub for more historical information about Decommissioned SCPs and their usage in the past.

Object Class FAQ

What is the Locked Box Test?
The Locked Box Test is an informal guideline used to determine an object's most appropriate Object Class. It goes like this:

  • If you lock it in a box, leave it alone, and nothing bad will happen, then it's probably Safe.
  • If you lock it in a box, leave it alone, and you're not entirely sure what will happen, then it's probably Euclid.
  • If you lock it in a box, leave it alone, and it easily escapes, then it's probably Keter.
  • If it is the box, then it's probably Thaumiel.

Note that as a special consideration, something that is autonomous, alive, and/or sapient is almost always at least Euclid-class. That is, if you lock a living thing in a box and forget about it, it will eventually suffocate or starve to death, and that's not a good outcome. Something that is intelligent could also end up being smart enough to outwit its containment procedures and/or stop cooperating with the Foundation's attempts to contain it, making it more dangerous than it otherwise might be.

What if I find an SCP that is the wrong Object Class?

The Object Classes are intentionally left vague as to not limit the author's creative freedom; a rigid, defined system of classes might hinder an author's ability to write the way they would want to, and as such multiple proposals to create better-defined systems in the past have been turned down by SCP Wiki staff.

If you find an SCP article that you feel might be inappropriately classified, feel free to raise discussion on the topic and see what other community members think. If the explanation is not to your satisfaction, then feel free to express your opinion on the matter and vote accordingly on the page.

If an SCP is very dangerous should its Object Class be higher?

No, danger does not really affect an SCP's Object Class. As has been reiterated several times above this, an item's Object Class is more based on the difficulty of containment rather than the danger it otherwise poses. For example, a button that can destroy the entire universe when it's pressed would be safe, whereas a cat who randomly switches places with another cat anywhere on earth would be considered Keter.

If you have any other questions about Object Classes, feel free to ask in the discussion.

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