[Userscript] Item Difficulty Indicator 🟢🟡🟠🔴

:warning: This is a third-party script/app and is not created by the WaniKani team. By using this, you understand that it can stop working at any time or be discontinued indefinitely.


If you don’t like to read, you can just install the script here:

What the heck is this?

This is a userscript that shows you the difficulty of items on a scale of 0 to 10 that you learn with WaniKani based on the experiences/difficulties other users had with them. This can be useful to find out if you should read an items mnemonics more carefully when doing lessons or to know if other people struggle with that item too.


This is how it looks out in the wild (while doing lessons):

Here is an example of how it looks on the info page and just some more examples:

There are still some items which do not have a difficulty rating (for example all radicals and some new items), they have a greyed out difficulty rating:

You can even decide on your own style (although this one makes me a little uncomfortable):

Image of settings menu for this script to change the style (powered by wkof)

You can get to it by clicking the gear while doing lessons or reviews:

This is how it looks:


Q: What are the difficulty levels?

A: The difficulty ranges from 0.0 to 10.0 (with a precision of one decimal after the point). There are 4 colors that correspond to the 4 difficulty levels which are shown depending on how difficult the item is to get correct. These levels are 0.0 to 0.9 (easy, green), 1.0 to 2.4 (medium, yellow), 2.5 to 4.9 (hard, orange), and 5.0 to 10.0 (extremely hard, red).

Q: How is the difficulty calculated and what does it actually mean?

A: The difficulty was calculated by the data I collected from the Wall of Shame of 89000 WaniKani forum users (see this thread: New Combined User Statistics!). The difficulty rating of an item is the percentage of people who have that item on their Wall of Shame (scaled so that the most difficult item of each level has 10.0). I had to scale it level-wise because the difficulty for earlier levels can’t really be put in to the same scale as that of the later levels.

Q: On which pages does the difficulty rating appear?

A: While doing lessons and reviews the indicator is in the lower left of the screen. On the info pages of the corresponding item it’s in a separate section titled “Difficulty”. Also, the visibility in reviews is changeable through the script settings, so if you don’t want to see the difficulty rating for every review or just after giving an answer you can choose to do that as well.

Q: Which items have a difficulty rating?

A: All kanji and vocab items that were introduced before November 2022 and sadly no radicals (because they don’t appear in the data I collected). E.g. 大人 (vocab) and 木 (kanji) have a difficulty rating, but 日の出 (vocab; introduced December 2022) and 工 (radical) do not. In total, there are 8609 items with a difficulty rating.

Q: What is the difficulty distribution?

As stated, there are 8609 items that have a difficulty rating. Out of those, 5495 (63.8%) are easy/green, 1688 (19.6%) are medium/yellow, 900 (10.5%) are hard/orange, and 526 (6.1%) are extremely hard/red. Also, there are 133 items that have a difficulty rating of 10.0. Because each level has at least one kanji 10.0 and one vocab 10.0 there must be a minimum of 2 * 60 = 120 of difficulty 10.0 items.

Q: Is it customizable?

A: Yes, highly! If you have the WKOF installed then you can access the settings through the gear icon in the top left (while doing lessons or reviews) otherwise you can edit them at the top of the script itself. The size, the colors for the difficulty, and even whether it has this bulky traffic light style is changeable. Please check out the settings to make sure they’re right for you! Also, you can decide if the number in the indicator has a decimal place after the point (with this style you can still hover over the indicator to get the exact value) and make that number more / less visible.

Q: Why did you make it?

A: At first, I just wanted to make this for myself because I wanted to see how difficult an item is for others or if I’m the only one struggling with it. But then it became quite fleshed out anyway so I polished it a little more and just decided to make it publicly available because I think there might be people who are interested in this kind of thing too. So have fun with it! :smiling_face:

Q: What about feedback?

A: Glad you asked. Please leave your feedback here! If there’s something I could improve on or even newly add I’d be glad to hear about it. Thanks :+1:


Clever idea. I like it.

I’ve never paid much attention to the wall of shame. How exactly does WK decide which two items show up there?

Since the WoS breaks out the percent correct for reading and meaning, did you consider separate difficulty ratings for each? I’m wondering if, for example, some item is on almost everyone’s WoS but everyone got, say, the meaning right almost 100% of the time (say a particularly unexpected rendaku).

While I like the idea, I find the information more of passing interest than anything. The SRS already does a great job of telling me which items I personally find harder than others (and letting me review those more often). Knowing whether or not others also found that item difficult sounds interesting, but I doubt I’d actually do anything different with the info. I’m curious if you feel it’s changed your behavior during your studies.


While I can only speculate on that, I suspect it’s either the lowest overall percentage (either reading or meaning) or the combined percentage of reading and meaning. But the first one would be more straightforward. This doesn’t really matter that much though because of the second point you brought up:

I saved all that info and then considered that as well. For example, if someone is just very good at memorizing and has no percentage under 90% for any item and then an item with like 90% reading and 100% meaning is on that persons WoS then this has only a minimal effect on the difficulty rating.

Well, that depends on interests imo. I personally like to compare myself with others (I know this is not really a good trait but I can’t help it :sweat_smile:) and thus it helps me to ease my mind knowing other people struggle together with me… well, this doesn’t sound nice, but it’s not the only reason I made this script, I swear!

For me, I often don’t realize that I have failed the same item over and over until it’s really one of my top leeches (maybe because I do the reviews too fast and/or often think that I was close to getting it right only to then get it wrong the next time as well). And this difficulty rating also helps me to remember that I have to think carefully about that item to not get a wrong meaning/reading engrained in my head.

Well actually, while I tested it out the last week it did wonders for doing lessons. I can “rush” through rather easy vocab lessons that are just compound words with an easy to memorize reading and take time for the items that sometimes even looked easy but turned out to have a catch that I would have otherwise noticed like way later. For me personally, it doesn’t only increase my lesson speed but also my mnemonic efficiency because I take time for harder items where I would have kinda rushed before. Obviously, it’s not actually a good idea to rush at all when doing lessons but the time save is real and sometimes I just don’t have the motivation to spend more than 3 minutes per item.


Great idea! A couple of small bugs:
SRS level popups are offset to the right making them stick off the screen
And the text inside it seems to change to a different colour each time lmao (red text on green circle, green text on orange circle, white on orange, etc)

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Ohh, I offset the SRS level popups because they were hindering the mouse-over-hover-text of the indicator. That worked for me but maybe I’ll just remove it because it apparently does more harm than good…

Okay, I pushed a new update. This should be fixed now!

Isn’t this because of the style you’re using (WaniKani breeze dark, I believe)? It inverts the colors, right? Maybe I can check for if this style is active and then invert the colors myself. Hmm :thinking: I’ll have a think on how to fix that!

Edit: I found a way to do that! Version 0.10 has the fix.

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Oh, didn’t think of that. If you could add in a check for that it would be great, but no rush!

Long off-topic discussion of this point

Apologies for wandering slightly off-topic, but this is an interesting point.

I’m one of those weirdos who never pays much attention to leeches. I’ve seen some items an AWFUL lot of times, but so far, even my very worst leeches eventually fall to sheer repetition.

On rare occasions, the penny will drop and I will realize I’ve seen something far too many times. I’ll then try to figure out right then and there why, and then try to do something about it (seeing if I’m confusing it with something else, disambiguating the meaning, repeating the reading a dozen times in my head, associating something visual in the character with the sound or meaning, whatever). I’d say this has happened maybe 20 times in three years. I honestly don’t worry about it much. If I don’t realize I’ve seen it a hundred times, I don’t really consider it a leech (it’s just something I’ll need to review a lot before it sticks).

Somewhat more often, I’ll get a little shock when something is marked incorrect that I was fairly certain I got right. That’s almost always because I’ve confused it with something else. Getting it marked wrong clues me in that I’ve got a “hash collision” (figuring out what I’m confusing it with is sometimes challenging, but it’s a win when I at least realize it’s happening).

And, of course there are the inevitable and all-too-common rendaku-or-no, nin-or-jin, consolation-or-condolence, etc. These, though, are best addressed via sheer repetition (IMO – though user synonyms for that last example are sure tempting). I don’t sweat it when I get these wrong (though I’ll sometimes answer them incorrectly multiple times just so they fall back further – I want more reps!).

But no matter what, if I see something enough times, I’ll eventually memorize it. Often as not a “leech” is just something that hasn’t dropped back to a low enough stage (I don’t see it in my reviews often enough, so I haven’t yet had enough reps).

That makes sense: it’s more a tool for lessons than for reviews.

Even more off-topic digression

But I think there are roughly two schools of thought:

  1. Work hard on mnemonics and try hard to recall during reviews. (Slow-paced lessons/reviews, fast progress through levels)

  2. Rely mostly on repetition. (Fast-paced lessons/reviews, slow progress through levels.)

I’m most definitely in the second category.

I tend to rush through all my lessons, anyway. Knowing others found an item easy or hard probably wouldn’t affect my lesson pace (YMMV).

Personally, I find new kanji the hardest (I rarely do more than 5/day when I’m only getting new kanji in my lessons). Even then, though, I put in just enough effort to get them into my review queue. These days, I rarely even bother with mnemonics – I depend entirely on sheer repetition (which is augmented with self-study — see below).

My own personal habit is to rush through both reviews and lessons. I ALWAYS do lessons after my morning review session (I tend to have just one session every morning, but try to do a second session later in the day whenever possible).

A while back I started doing self-study for items in stages1-4 (or just 1-2) before starting my real reviews. Getting in more “reps” for early-stage items like this has done wonders for my overall retention (and even sped up my time on each level).

My personal opinion is that instant recognition is always the goal. If I have to struggle to recall something, it means I’ve not had enough repetitions. Burning something before I get to the instant recognition stage is my biggest annoyance. [I really should install a script so I can mark things incorrect when I burn them earlier than I feel is warranted.]

To make a lame attempt at bringing this back on-topic: I can see that some people might find that this script speeds up their lessons. Personally, I doubt it would change my habits, but I find the information it presents interesting, regardless.

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This is a fantastic idea.
I won’t use it myself because I learn and review exclusively on mobile through the FD app, but if it were available in the app, I’d use it for sure.
Without even having used it, I can safely say that it would have a positive effect on both speed and retention.


Thank you for your feedback, that makes me really happy to hear! :grin:

Answer to the long off-topic discussion

Honestly, what you said hits close to home. It’s the same for me, maybe it’s just natural and the same for everyone, who knows. Now that you say it, I think you’re right in that even with this script many people would still not have it a great deal easier with leeches. I guess, it depends a lot on the person if it can be useful.

Answer to even more off-topic digression

I guess I’m in neither of these two schools of thought, I do fast-paced reviews and lessons and I still managed somehow to get through the first 30 levels pretty quickly. Although this isn’t really a good idea because it really comes back to haunt you later with huge piles of reviews.

I catch myself looking at the mnemonics less and less, like you said (even though that was supposed to be the thing I’m paying for here haha). I really agree with what you said that ultimately instant recognition is the goal. Personally though, I can’t achieve that with only WaniKani (or any SRS system for that matter), I always have to read it in the wild to recognize it. And in order to start recognizing it in texts at all it’s always good to be able to connect it with a strong stimulus; for me such a difficulty rating does this pretty well and if I see an item with a high difficulty again I’m just more likely to remember it in order for it to go over into “instinctive” memory.

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Would it be possible to hide the indicator while doing reviews (maybe until you get something wrong)? I would rather not have something that helps me get answers right that won’t be present in the wild.

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found a ten :eyes:


I suddenly imagined, what it would be like to go around Japan, and everything has a small circle with a random number in it. Sounds fun


I made a few settings for a user to be able to tweak that and related things. You can now hide the difficulty rating for reviews away in the item info or just make it show when you answered (correctly or incorrectly).

Images for new settings

Here’s the new settings section:

With these settings the difficulty rating would be down below in the item info:

For the functionality you want these would be the settings:

With these settings the difficulty rating will be greyed out until you answer:

Oh yeah, that should be fixed now too! (hopefully) Does it work for you as well?

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oh! :eyes: That word appears in the OP of Bocchi the Rock. It’s a good song.


Source: 結束バンド 青春コンプレックス 歌詞 -【歌詞リリ】


I use WK Double Check for this.


I like the idea :slight_smile: Trying this out, but I can’t seem to get the difficulty to appear on the item info page (see screenshot below). Lessons page work fine.

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damn I literally just listened to that, guess I should pay more attention to the subs


Do you know of the settings for the script that you can change in the top left when doing reviews (there should be a gear icon). Settings → Item Difficulty Indicator and then there should be a setting called “Show on Info Page” which should be true.

Did you try this? Maybe change the setting to be the other way around just to be sure. Hope this helps and please report back if it still doesn’t work!

installs immediately

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Very minor bug: When you select “Hide Difficulty until Answered” when Indicator Position is “In Item Info”, a warning message pops up (as it should). However, if you then change the Indicator Position to “Beside the Character”, the warning message stays even though it is not valid anymore.

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