When I did did a brief stint of French study, I specifically switched up which spaced repetition system I was using, so that in addition to learning some French (mainly just that French is a lot harder than I thought), I also gained breadth of knowledge in spaced repetition in general. The first SRS I used, and which I still use regularly for my Japanese card deck (now two or three years old), was Mnemosyne. The one I used for French was Anki.

If you don’t know what spaced repetition software is, you should click that link above, but in a sentence: spaced repetition software is a digital flashcard system where you create and review flashcards and the software optimizes the bejeezus out of the review process, showing you cards in the optimal possible order so you can memorize the most data with the least effort.

Which is better, Anki or Mnemosyne? Let’s compare a few aspects of these two memory programs.


Anki wins hands down for aesthetic appeal. It has the look and feel of a professionally built commercial application (even though, like Mnemosyne, it’s free). Mnemosyne has the bare bones look and feel of something a grad student whipped up for an obscure research project. (Grad students, please don’t feel offended, I’m one myself!)


For pure text cards, Mnemosyne is easier: you can “tab” your way through the whole process. Unfortunately, in Anki if you start “tabbing”, you’ll go through “tags”, “model”, “add a new model”, “edit the current model”, and “forward” before finally getting to “add”. That makes tabbing impractical; I don’t even know why it’s done in this order, since a person would almost never touch the model-related buttons. You can do a mouseless-card-add in Anki using shift-ENTER, but that’s not very intuitive.

However, if you’re adding multimedia flash cards, Anki has a brilliant feature where you can just paste the URL of the file on the internet. Anki will automatically download it and store it in a data directory, all quite seamlessly. When I was adding picture flashcards to Mnemosyne, it was a horribly convoluted process of manually downloading the pictures and then manually writing the html code for them in the card. Anki’s method is almost instantaneous, and it saved me a lot of time.


Mnemosyne flashcards can be imported directly into Anki, but Anki flashcards cannot be imported directly into Mnemosyne. However, if you did want to import an Anki deck to Mnemosyne, you could first “export” the Anki deck into a tab-delimited file. An extra step, and any info about your card ratings would be forfeit.


Anki seems to be updating constantly. When I was doing my French Revolution Challenge, a bunch of people from the Anki “community” were following along, and some updates were released based on the feedback I was reporting, within days of my reporting it. Makes me feel pretty good :) Mnemosyne, on the other hand, hardly ever updates.

On the flipside, though, I’ve gotten emails from people complaining that the Anki updates sometimes change the controls, so if they keep up to date, they’re having to constantly relearn how to use their own SRS. In that sense, Mnemosyne is more “stable”. Of course, it should be emphasized that, officially, Anki is still pre-version-1.0 (as of the time of my writing this). Usually software stabilizes a lot after it reaches version 1.0.


The two systems are pretty similar as far as ease of review goes. Anki does have some extra data displayed, however. Anki splits up “remaining cards” into “failed cards”, “cards awaiting review”, and “new cards added today”. Mnemosyne clumps these same cards into just two categories, “scheduled cards” and “not memorized cards”. Anki also has some “power bars” which attempt to measure “how good you’re doing”, although they’re not too reliable.

One feature Anki has, which really blew me away, is the “ETA” display. Somehow the program looks at how fast you’re answering cards, and makes an intelligent guess how long it’ll take for the “scheduled cards” to hit zero. In my experience, ignoring cases where you get up in the middle of a review, the ETA seems to be pretty accurate.


The heart and soul of the SRS, what sets it apart from paper flashcards, is the algorithm it uses to transform your own ratings into an optimized card ordering. If you rate a card easier, it should show up less often, and so on.

It’s not easy to get a perfect sense of an SRS’s algorithm, since it all takes place behind the curtains. Anki’s algorithm seems to be marginally better: if nothing else, it’s a lot more customizable. You can adjust all sorts of numbers to get Anki’s algorithm working the way you want it to work.

On the other hand, Anki has a “feature” where cards come due in realtime, rather than day-by-day. This sounds like a cool concept, and maybe it could be if it were somehow implemented differently, but to me it ended up being a nuisance. The main problem is, when I sat down to do my daily reviews on Anki, I had no idea how many cards I’d actually have to do, because new ones kept coming due in the middle of the review.

The day-by-day scheduling of Mnemosyne is not just an arbitrary constraint. Fact is, the process which transforms raw, rote-memorized data into structured, meaningful data, this process takes place while we’re asleep. You can force yourself to memorize something today, and it seems like just raw gibberish, but somehow after you sleep on it, it makes a little more sense, in a way you can’t quite explain. (I wrote more about this in my article, The Irregular Verb.) The point is, there’s a very real reason to make cards come due day-by-day rather than minute-by-minute.


For statistics, Anki wins hands down. It even makes fancy graphs and pie-charts, if you want. If you’re using it to study Japanese, you can even get some very advanced kanji statistics (to enable kanji statistics in Anki you need to make sure your Japanese cards actually use the “Japanese” model).

On the other hand, if you only want the statistics infrequently, and don’t mind a little hassle to get them, you can get Anki statistics for a Mnemosyne deck. That article explains how.


Spaced Repetition Systems
Multiple SRS Decks
Neglected SRS Decks


  1. Todd says:

    Regarding “invisible” text: I’ve never used Mnemosyne, so I’m not sure why this trick is necessary, but in Anki you can simply add a field to your model but not use it in the card template. If you want to read it, simply click “edit” while reviewing the card (which, as I understand it, is the same way that your invisible text method works).

    • Xamuel says:

      Yes, you’re right, I just don’t want to bother doing that for ~10000 cards and there doesn’t seem to be any reasonable way to automate the conversion process