I wrote my own chart utility to track my progress, because none of the options I could find were as simple and straightforward as I needed.
Here is the utility: Zenshin for Wanikani
And this is what you get:
The blue section shows your level completion progress, while the gray part is a forecast based on an exponential moving average, with a bracket of two different alpha coefficients (in my case above they happen to coincide, but in general you should get two distinct grey lines.)
The vertical red line is today.
The red squiggly line shows you the speed at which you’ve been progressing, in levels per month. The maximum value is around 4.5 (1 level per week) although the right-side axis goes up to 6 for graphical reasons.
All in all this is a simple way to see where you are in the journey and when you can realistically reach the various levels, assuming you keep advancing at the same pace. It’s also a way to encourage yourself not to “slack off.”
Warning: if seeing a chart that is mostly gray or with dates several years from now will discourage you, do not use this app.
The website needs an API key (without any further permissions) and only stores it in your browser. The code is open source, you can check on Github and even rebuild the app if you are paranoid.
As a consequence of this, I have only access to my own account, so if you spot any issues on yours, please post a screenshot.