Another in the series of "stuff about the site I thought people realized this about the site, but recent interactions lead me to suspect not that many actually do". Each image added to Civitai is scanned and automatically given an age rating. Most of the time this works as intended, and ratings are correct, but sometimes it’s dead wrong
If you feel a rating is wrong, you can actually ask to have it changed. To do this click on an image to open its attributes, then click on the rating (e.g., PG-13) and click what you feel it should be rated. This will be sent to a queue and, if whoever is doing the queue agrees (not sure if it’s manned by mods only or if people playing the Rating Game see them/have an impact) the rating will be changed (It’s possible the new rating won’t be the one you submitted. For example an image that is auto-rated R you say is PG might get a PG-13 rating). The queue itself will take a long time (possibly as long as 24 hours+). This delay (alongside various system lags and the file scanner sometimes stalling occasionally choking new LoRAs that get instantly published) is why I schedule my LoRAs for several days in advance, though I understand this is not an ideal solution for people who aren't shoving out LoRAs so fast that they can queue up publication so long in advance.
You can also vote down inaccurate tags by clicking the arrows next to them. This includes both incorrect rating tags, as well as tags that are just wrong (tomboys being labeled male). You can even add tags by clicking on the +TAG button next to it, but since they start at too low a threshold for anyone else to see them or them to have an influence unless multiple people add the same exact tag, I doubt this is actually worth bothering with.
Appendix: Misc stuff on age ratings:
While I'm here, might as well post this stuff
Common sources of particular ratings:
PG-13=navel, cleavage, or short skirt/shorts
R=Underwear, swimwear, leotard, nude figures with the naughty bits covered (?). In the past topless but otherwise clothed within R females were placed in this category, but I’m not sure if modern images with such being placed in X now is an intentional shift or just a causality of tweaking how this piece of the site.
X=Nudity, otherwise R+ material involving a couple (?)
XXX=Sex, sexual presentation
Common sources of false positives (by rating given by site):
Any: Part of the prompt is incorrectly read as a word that carries a particular rating. For example a LoRA for a certain fictional detective or the style of a work starring him might use might use “Dick_Tracy” but the scanner just sees “dick” and doesn’t bother to check if the image actually has any (I recommend creators using arbitrary tags that don’t contain unobfuscated real words/names for this reason among others, but this can’t be changed after training so some resources are stuck with it). Even without extra resources, there's a few tags prone to false positives like giving an armored character a "pelvic curtain".
PG-13: Skirt/short length (this one is, by far, the biggest error in the auto-rating and the most impactful)
R: Clothing wrongly thought to be underwear/swimwear (such as some crop tops), clothing that is strictly underwear/swimwear but non-elicit (e.g., bottom of long bloomers, full SCUBA gear), underwear/swimwear not worn (e.g., on a mannequin, held, on floor), human figures illustrated from above the armpit with no obvious clothing, non-sexual shirtless men (e.g., fantasy characters, boxers and similar athletes)
Now you may wonder what the practical effect of an image’s rating are. I know the following:
PG images are shown to viewers who aren’t logged in or are viewing on Civitai Green. A resource’s gallery needs at least one image with a PG rating to be shown to such users. PG images will have ads served on them. PG images can be entered into daily challenges as well as all contests (though as a practical matter getting an image appealed in time makes relying on this a dubious tactic. Feel free to try if you think it's awesome, just have enough entries without it to get to in without it). PG is also required to be posted on certain types of resource (those tagged real person or no NSFW) but those are automatically sent to the mods anyways when the system sees them as PG-13+ so I don’t think disputing their rating matters. You can still vote down false positive tags, as from what I’ve seen whoever it is that rating appeals go to never clean those up).
PG-13 images will have ads served on them, but will only be shown to users logged in to the main site, and some site contests have allowed them to be entered. I’m not entirely sure how PG-13 images on LoRAs voluntarily marked no-NSFW is supposed to work (I have previously recommended that resources tagged no-NSFW allow these without being sent to queue because of the sheer rate of incorrect PG-13 images due to skirt/short length issues, but that doesn’t look to be getting implemented).
R, X, and XXX images don't have ads on them, and if they're the cover image of a LoRA that LoRA does not contribute to most (any?) leaderboard(s) other than Creators (Mature). To my knowledge, the distinction between R and higher is purely for user filtering.
Update April 19th: Various smaller tweaks