there’s no really straightforward formula, because you have to take into account both the time per level, and the items per level (which vary widely). but generally i think the 15-16 lessons per day ought to work, and then front-load your radicals when levelling up so that you don’t end up waiting unnecessarily for your items to guru ^^
Not true. I can easily level up in 8-9 days doing 20-25 lessons per day max. Just need to have them in the correct order.
How would I go about doing this such that I don’t forget everything if I have 60+? Could I split it up between the morning, afternoon, and night so that I get reviews after each set of ~20 (if it was a big unlock day).
I’m not a fan of going slow and routines, but 60 lessons in 1 day seems like a pretty bad idea to me. If you unlock a new lesson, you can use the mobile app to study the new lesson radicals before studying the older lesson vocab to avoid slowing down your progress. Scripts could also work for that, but I never used any.
So basically all you need to go as fast as possible is doing radical lessons as soon as those are available, then doing kanji that require those radicals. Kanji that are available as a lesson unlocks can be done at any time, but not later than those, that require radicals to unlock (I prefer to do about 10 new kanji a day). That’s it. You can do the vocab whenever you want. In any chunks you want, but most ppl don’t consider it a good idea to let your vocab fall behind too much.
That seems like a good way to do things and that makes sense about the radicals. I will keep that in mind, thanks!
Yeah, then I don’t know how I reached level 60 in 1 year with only 20 lessons a day 
@Ikiga1, like people have suggested, 15 lessons a day is a good target. Read my Guide for Wanikani, mainly chapters 4-8. I explain everything on how people can do a very reasonable amount of lessons a day and still reach level 60 pretty fast (without skipping any items whatsoever).
I will check it out, thank you!
Was that with some sort of script to get all the radical and kanji lessons first or did they change how it works since I did it?
I basically did a cycle of 7 days (a week) per level. The trick is to basically do radicals the moment you level up, and the available kanji lessons throughout the first 3 days. Vocabulary lessons are done in a balanced distribution during the whole level/week. The moment you guru your radicals, you do the lessons for the kanji that unlocked (usually they’re very few). Each level has 2 cycles of 3 days and 12 hours during the level (it takes that much to go from lesson to guru).
This is achieved by using a reorder script, but I believe even the non-official apps allow you to do that nowadays. Even without any script and go going by the “Ascending level then subject” order (an option in the settings), you could still reach level 60 in 1.5 years with 20 lessons a day or less (and you’d have days without lessons available).
I do this but I don’t use a reorder script. I do the lessons for the vocabs from the kanji that I just guru’d from the previous level until I get to the radicals and do them as soon as I level up. Then when my radicals are guru’d my kanji automatically shows up before the vocab on that level that I haven’t done yet. Pretty neat.
Is there any particular reason to wait to start the kanji lessons until the radicals are reviewed? Is it just to reduce inaccuracies later on that could save time overall if prevented by having radicals better locked in?
The main reason to reorder lessons to radicals first is primarily to reduce the time in takes to complete each level.
In order to level up you must Guru 90% of each levels kanji. However, some kanji aren’t available to learn immediately, they’re locked until you guru the radicals first. For most levels more than 10% of that level’s kanji are locked behind the radicals, so doing any other lessons before radicals adds more time to your level up time.
Radicals unlock Kanji once guru’d, Kanji unlock vocabulary once guru’d.
Note: reordering lessons to do radicals first is the most efficient method, but that doesn’t necessarily make it the best. If you don’t keep up with your other lessons it can lead to a build up of lessons from old levels.
So just to clarify, I would be waiting until all radicals are guru’d to start kanji lessons, so about two days without (kanji) lessons (assuming I continue the vocab lessons), correct?
Also, is it okay If I miss 2-3 radicals each review?
No, you’ll still have Kanji lessons for radicals you’ve guru’ed in previous levels. Those are unlocked immediately.
The radicals for a particular level will unlock the second group of Kanji for that level.
As long as those radicals correspond to less than the number of Kanji you can miss to level up.
Note: You won’t have to worry about this for a while, but the fast levels from 44 on up don’t have this limitation. You’ll get all the Kanji right away.
I apologize, but I believe I may be misunderstanding the process. I just reached level 5 and have gone through all kanji from the previous level, though I still am getting new vocab lessons. I did all of the radicals and most are up to level three. Where do I go from here? (I may be wrong, but I believe level 5 only has one kanji with old radicals which is 兄)
Ah yeah, i think the split isn’t even if you’re below level 10 because you don’t have a lot of total radicals in Guru yet. So the second half of Kanji will be the bulk of it until then.
So at this point then if don’t start the kanji until it is released once all of my radicals are guru’d and wait to start vocab until all kanji are guru’d, then that should be alright, correct?
Also, looks like you just reached level 60, congrats!
I wouldn’t worry about that too much. Just keep going at a pace you can handle. You’ll figure it out along the way. If you can do those 16 or so lessons a day, there is no way to not be done in 1.5 years. If something stops you from doing those 16 lessons a day, then you can start looking for solutions. A problem has to exist to possibly require attention.
Did you read the guide? Mainly chapters 4 to 7. They have the answers to your questions.

There’s no need to wait until they’re guru. You can do radicals on Day 1, on Day 2 some of the kanji lessons, finish the kanji lessons on Day 3, and then do vocab throughout the level as you see fit.
Thanks! 
Looks like @jprspereira already answered, and he’s pretty much the authority on the subject IMO.