This **spaced repetition** made me really curious about the math in learning a course on Memrise.

I’m not sure if these numbers are outdated for spaced repetition:

After you learned a word, it will occur again in 4 hours. When you got it right after 4 hours, it will occur again in 12 hours, and then in 1 day, 6 days, etc. I’ll just list the whole thing.

4 hours

12 hours

1 day

6 days

12 days

24 days

48 days

96 days

180 days

180 days

180 days

It seems 180 days is the cap for Memrise’s spaced repetition.

Assuming these numbers are still applicable and my calculations are correct, for a 2000-word course and learning 100 words a day, and let’s say you start learning the course on January 1st. You’ll also learn the course every day [including **Saturdays and Sundays without any flaws** and the **timing is perfect** that is to say you review the words immediately when it’s time to review and more importantly, you review all the words needed to be reviewed]. You’ll finish the course on **January 21st**. Also on the first days, you’ll be learning twice or thrice as much work at the beginning of the month [circa January 2nd to January 27].

From January 2nd to January 27, it’s expected that you will be having 200-300 words to review every day. After January 27, it’ll drop to 100 words per day until February 8th. The highest amount of words to review in a day is 400 and that day would be January 20th. It’s the only day that you’ll be getting 400 words to review.

Then you’ll have a 4-day break from February 9th to February 12th. Reviewing starts again on February 13th and ends on March 4th. It’s expected that you have an average of 100 words to review every day in this session.

After March 4th, you’ll have a break of 28 days, and reviewing starts again on April 2nd and ends on April 21st. The average words to review per day is 100.

After that you’ll have a break for **76 days!**

Next reviewing session is on July 7th to July 26th. The average words to review per day is still 100.

And then another break for 160 days. Does this remind you that you’re reaching for your 180-day spaced repetition? Well, in the next session of reviewing, you’ll be **finally** achieving your 180-day gap.

Ok, the next session is going to be on January 3rd the next year and ends on January 22nd. Still, the average words to review is 100. And after the session, you’ll be having another 160-day hiatus.

And the next 180-day gap starts on July 2nd the next year.

I estimate the points you’ll be collecting in this very long span of time would be 3,300,000 in this single 2000-word course from January 1st to July 21st the next year.

How did I get these numbers? I used a calendar and wrote numbers on them and added them. Haha. Also, a good calendar is the year 2017 because January 2017 starts on a Sunday. But I hope my analysis and computation is correct. I might have got some errors in the way.

Anyways, thanks for reading this bizarre and nerdy post, and have a nice day.