Can I have too many mods?

Question

I found a lot of mods that make thinks lighter, and add mark and recall, and a basement I like. They are all on Steam, and what I want to know is if I can have too many? Will they all work together? Or should I just leave them alone?

Answer 1

The number of mods Skyrim can handle seems to be limited by an unsigned byte, meaning slightly less than ~256 mods (One account on the Bethesda Blog, now unavailable, says 252 accounting for Skyrim.esm, the Update.esm, and the Saved game).

If you need more, some tools such as Wrye Bash can combine mods together, but this means you will need to manage these mods outside of Steam Workshop (Vortex Mod Manager and Mod Organizer (SKyrim SE/LE) are some options).

Previously there was a 50 mod subscription bug with Steam Workshop, but it looks like Update 1.4 fixed that issue.

Answer 2

Oblivion and Morrowind where limited to 255 mods, so we could assume that Skyrim have the same limit too. That said, 255 is still a rather high number, so unless you're grabbing every mod you find, you should be fine.

As for compatibility, it really depends on the mod and the load order. Some mod may work without problem, others only in a certain order, and some others just won't work together. It is a case-by-case problem, so you should carefully read the README of the mods, and you should try using tools such as Wrye Bash to keep them organized.

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Update for 2024:

Following the release of Skyrim SE and the Creation Club content (Archive), the answer changed a bit. Bethesda introduced the ESL mod format, which have limitations in term of what they can change in the game, but have a different identifier structure, so they do not compete with ESP and ESM mods for IDs. This allows them to go over the limit. They have their own maximum number, which is much higher (4096 since 2023)

Here is an overview (Archive) of each limit, with more technical details on why they exist and some workarounds.

Answer 3

I'm going to provide some more detail on how ESL and ESM files work and what the limits are, just to make sure we have an on-site explanation of the current (2024) state of affairs (but the links in Jupotter's answer are also very useful, so go check them out too). Internally, ESL, ESP, and ESM files (collectively, "plugin files") are all really the same file format, but have "flags" in their headers that tell the game what kind of file they are. The file extension is also consulted, but for reasons known only to Bethesda, the engine consults the header for certain purposes and consults the file extension for other purposes, leading to more than three kinds of file in practice. xEdit can be used to toggle the flags, so modders have experimented with different combinations. Here are the kinds of file that you are reasonably likely to encounter:

• *.esm file with ESM flag. Vanilla provides five of these files, and some new lands mods are also provided as ESMs. They are never allowed to override another plugin unless it also has an ESM flag, so they behave as if they are forced to the top of your load order (many load order sorters will move them up automatically to avoid confusion). Sometimes called a "master."
  • I'm not going to list all the other combinations of the ESM flag and other file extensions, because they're not used much in practice. In the past, I think the ESM flag may have occasionally been used to stop people from loading ESP files into the Creation Kit, but this is no longer effective because there are now mods of the Kit which disable that check (and xEdit never respected it in the first place).
• *.esp file with no flags. This is the standard kind of ESP file that is produced by the Creation Kit by default. Prior to Special Edition, this was the most common type of modded plugin file.
• *.esl file with ESL flag. This is the kind of plugin used by Creation Club, and they are very occasionally used for plugins that don't edit vanilla (for example, because the plugin only contains keywords or other ancillary data that is used by other mods, or because it only exists in order to load a BSA archive). Like ESM files, they are never allowed to override an unflagged ESP, but they can override ESM and ESL files. Sometimes called a "light master."
• *.esp file with ESL flag. Hybrid of ESL files and ESP files, described in greater detail below. Sometimes called an "ESP-FE," "ESL-flagged ESP," or "light plugin."

The limits on how many plugins you can have are determined based on how form IDs and reference IDs are assigned. For files without the ESL flag, on the Special Edition, every plugin controls all form IDs with a given two digit hexadecimal prefix. These prefixes start from 00 and count up to FD, for a total of 254 possible plugins (without ESL flag). For files with the ESL flag, regardless of file extension, every plugin controls all form IDs with a given five digit hexadecimal prefix, starting from FE000 to FEFFF, for a total of 4096 possible plugins (with ESL flag). Finally, the FF prefix is reserved for "temporary" objects which are created after the game starts (e.g. using placeatme or the Papyrus equivalent), and I believe it may also be used internally to assign IDs to some objects that only exist in save files, such as changeforms. As a result, no plugins are allowed to use those IDs.

The special property of *.esp files with the ESL flag is that they get to play by both sets of rules:

• They are loaded into the FE space, which allows a larger number of plugins (but each plugin is given fewer IDs to play with), just like ESL files.
• They are allowed to override other ESP files, unlike ESL files.

However, there are sharp edges to this:

• You can't ESL-flag anything with too many new records. Override records do not count towards the limit, so the ESL flag is commonly deployed for compatibility patches and other mods that are mostly overrides. Using it on other mods is a bit of a gamble, because if the mod ever outgrows the ESL limits, some end users might not have a full plugin slot ready for it.
• When applying the ESL flag, you need to ensure that all of its form IDs are low enough that they will not conflict with the FExxx prefix. The Creation Kit, for reasons known by Bethesda, does not start at zero (or 0x800, which used to be the safe lower limit) and count up, but instead seems to assign more or less arbitrary numbers, sometimes resulting in plugins containing invalid form IDs when the ESL flag is applied.
  • xEdit has a script that can "compact" form IDs, moving them all down to the lowest suitable number, but this will break existing save files which have been run with that mod (because the IDs in the save file will not match the plugin's IDs).
• A bug has been identified involving ESL-flagged ESPs which contain new CELL records, and are subsequently overridden by other ESPs. The current advice is to avoid using the ESL flag on any ESP which introduces a new CELL, just in case an override ends up happening later in the load order, unless you're completely sure that no such override exists and you've already ESL-flagged everything that can be ESL-flagged and still need more plugin space. As a courtesy, it is recommended that you avoid distributing such mods with the flag enabled, because it can be very confusing to debug.

And, finally, excessive ESP files, regardless of the ESL flag, may cause infinite loading screens and other problems. This is dependent on the total number of references (objects or NPCs) added by all ESP files, and not on the number of ESP files. Conversion to ESM or ESL is the only known way to mitigate this problem, but this is complicated by the fact that some mods accidentally depend on the very behavior (forced persistence of all references) that we're trying to eliminate. This tool is a good starting point, but you will probably still need to do a certain amount of trial and error. This does not change the total number of plugins you can load, but it does potentially increase the amount of work you will have to do to load them without crashing your game. Fortunately, this only affects people with a huge number of modded references, and the linked Reddit thread provides an xEdit script that will tell you how close to the limit you are. If you are not close to the limit, my advice is to entirely ignore this paragraph unless and until you massively increase the number and scope of your installed mods.

Answer 4

it depends on the mods. Remember, mods are made by random people. If you're lucky, they do enough quality control on their own works, but most probably they don't care about other mods (unless they're really really famous). So recommendation, just use what you really need.

Answer 5

Only subscribe to dynamic and constantly updating mods. For example, the dovahkiin hideout or midas magic, which keeps updating.

But for something like the paarthurnax fix or perfected weapon mods (that require no more attention), you unsubscribe but keep the data files so they remain in your skyrim but are no longer 'subscribed' as such.

Answer 6

Strictly speaking, there's no such thing as 'too many' per se.

However, mods can conflict with each other, and some do expand the demands the game places on your system (I.E. texture packs).

Other than known or obvious conflicts though (you DO read the README, right?), all you can do is try them and see. If you have issues after installing a bunch of mods, disable them one by one (or the reverse) - its really the only reliable way to troubleshoot.

Answer 7

I am using NMM and i can't run more than 255 mods, when i select 256th a msg appears that you can not use more mods. So i am currently running 255 mods with NMM..

But you can run as many mods as you want which don't need install (means the mods which don't have esp or esm files like the textures, sounds, meshes like stuff)