Just did 2 more unit test certifications and 3 honorary ones. Leaderboard count increased by just 2. So maybe honorary ones never count on the leaderboard and I was mistaken before about my AP Calculus and AP Computer Science ones having counted initially (I assumed they counted back when my theory was that the leaderboard count was the profile count plus 15 extra per course challenge).

My profile currently shows 83, which I think comes from

7 course challenges

69 unit tests

7 honorary certifications (counting SAT Prep: SAT Math and SAT Bootcamp Math: SAT Math as two different things, even though just SAT Math shows on my profile and it was a single submission that got me certified in both)

My leaderboard count is 183. If I assume honorary certifications don't count at all, then solving 7x+69=183 gives me x=16.29, so I'm not seeing a common integer multiple of the number of course challenges that explains the leaderboard number. So I'm basically back to where I started of not being able to figure out the leaderboard number except to say that a unit test certification adds one to both the profile count and the leaderboard count and (it appears) honorary certifications don't impact the leaderboard count.

OK, my theory that the leaderboard count was the profile count plus an extra 15 points for each course challenge certification hit its first snag after I got certified in SAT Prep: SAT Math and SAT Bootcamp Math: SAT Math (didn't realize the latter was a thing - getting certified in SAT Prep: SAT Math apparently automatically certifies you in the other). That upped my profile count to 57 (I've done a number of unit test certifications since my last comment). That 57, I believe, is from my 46 unit test certifications, my 4 honorary certifications, and my 7 course challenge certifications. But those final two honorary certifications don't seem to reflect on the leaderboard, where the count is 160, which is 55+7*15, with 7 the number of course challenges I've completed. Maybe honorary ones take longer to show up on the leaderboard for some reason (My AP Calculus and AP Computer Science ones appear counted), or maybe SAT certifications aren't counted at all in the leaderboard tally for some intentional or accidental reason. It's of course also possible that my made up rule of 15 extra "certification points" for every course challenge is entirely inaccurate, but that theory held true until SAT Math entered the equation today.

OK, just did a unit test certification in Pre-Algebra, a subject I had already done a course challenge certification in. Before doing it, I was at 119 on the leaderboard and 14 on my profile. Both numbers increased by 1 when my Factors and multiples certification went through. So that answers one question I had, where I wondered what would happen if I had a course challenge certification and then completed a unit test certification. I thought perhaps the leaderboard count would not increase, if my count already included all the unit test counts, but it did increase, so that theory is out. The "16 certifications on leaderboard for one course challenge certification" theory still could hold.

Edit - I wonder if the leaderboard count is simply the certification count shown on the profile plus 15 extra "certifications" for each course challenge certification. As I make this edit, I'm up to 39 certifications shown on my profile (as I'm doing a number of unit test certifications), and 144 on the leaderboard, with 7 course challenge certifications done, and 39+7*15=144. Some units, like Pre-Algebra, are composed of 15 individual units, so a 15 point bonus for a course challenge makes some sense. I don't think the profile vs. leaderboard discrepancy makes sense, but I'll go with my working theory on how the profile count is determined (the number of certification requests you've sent in and had approved, with unit test, course challenges, and honorary certifications all treated equally) and then how the leaderboard count is determined (15 bonus points for each course challenge certification) until proven otherwise.

I just did my first unit test certification, in a subject I had an honorary certification in, and can share some more data.

My profile count of 9 (which I assume came from 7 course challenge certifications plus 2 honorary certifications) increased by 1 to 10. My leaderboard count of 114 also increased by 1 to 115.

That suggests the leaderboard count is counting units, though as noted above I still can't explain the total count of 114 (now 115). It's odd that the profile count treats a course challenge as just 1, equal to a unit test certification, but perhaps the profile count should be interpreted as "these are the number of certification requests you've sent in and had approved," with unit test certifications, course challenges, and honorary certifications all treated identically and each counted as 1. I am curious what happens if I complete a unit test certification in a subject I've already completed a course challenge in - will both my profile count and leaderboard count go up, or will only my profile count go up because the leaderboard was already crediting me for the unit?

Another possible theory on the 114 is that perhaps a course challenge counts as 16 (for some reason), so 7*16 + 2 (honorary) = 114.

I have a similar issue. My profile lists three certifications but says I have five certifications, and the leaderboard says I have no certifications.