Why a slower, perfect Speed Cards deck beats a fast one with a mistake: how the first wrong card caps your score, and how to use your two attempts.
Speed Cards is the most famous memory sport event: memorize a shuffled 52-card deck as fast as you can, then recreate it in order. Your speed cards score is not just your time, though. It is a points value calculated from your time, and the rules behind it mean a slower, perfect deck beats a fast one with a single mistake. This is the strategy that follows. To convert a time on its own, use the Speed Cards points calculator.
For a deck recalled completely and correctly, the World Memory Sports Council scores:
Points = 11180 ÷ (time in seconds to the power of 0.75)
The constant is chosen so that a 25-second deck is worth exactly 1000 points. The best of your two attempts counts.
Here is the formula worked out for a range of times:
Five minutes is the memorization ceiling, so 155 is roughly the lowest score a complete, correct deck can earn.
Because of the 0.75 exponent, cutting your time in half multiplies your points by about 1.68, not 2. Going from 60 seconds to 30 seconds takes you from about 519 to about 872 points. That is a big jump, but a less dramatic one than the stopwatch suggests. It also means the gain from each second saved shrinks the faster you already are, so the last few seconds are the most expensive to find.
This is the part that matters most. The recall deck is compared against the memorized deck card by card, and only the cards before the first discrepancy count. If you recall fewer than 52 cards correctly in a row from the start, your time is treated as 300 seconds and your score is:
Points = cards correct ÷ 52
So a deck where you got the first 40 cards right and then slipped scores about 0.77 points. Not 77. Less than one point. Even 51 correct cards is under 1 point, while a complete deck at the five-minute ceiling is worth about 155. A slow, correct deck is worth more than 150 times a nearly-perfect deck.
Say you memorize a deck in 48 seconds and recall every card correctly. Raise 48 to the power of 0.75, which is about 18.2, and divide 11180 by it. You score about 613 points. If you had swapped two cards near the end, the first discrepancy would cut your count at that point, and you would score a fraction of one point instead.
A deck is 52 items, and each has to be turned into an image and placed in order. The time you record is the sum of three things: how fast you recognise each card, how fast you turn it into an image or scene, and how fast you place it on your route. Competitors often group cards, so that two or three cards become a single scene, which cuts the number of placements. That is why a deck can be memorized in far less time than it takes to read the cards aloud.
It also explains why speed comes in steps. Getting faster at recognising cards is one improvement. Making your images more automatic is another. Shortening the walk between locations is a third. Progress often stalls until you spot which of the three is holding you back.
Your memorization time runs from the moment you see the deck to the moment you stop the clock. Recall then begins, and you have a fixed window to rebuild the deck from a set of cards. Because the score depends only on the memorization time and on whether the deck is right, there is no benefit to rushing recall. Take the recall time you are given and check the order before you submit.
In the World Memory Sports Council format, yes: the better of your two attempts is your score. That is a useful licence to take a small risk on the second attempt if the first was clean.
Only the cards before the first discrepancy count, so guessing a card you are unsure of costs you nothing that leaving it blank would not. What matters is that every card before it is right.
No. Runs with fewer than 52 cards use the same rules on a smaller deck, but the numbers cannot be compared with a full deck. They are useful for building a routine, not for tracking a ranking.
The event score ranks competitors within Speed Cards. A different conversion, based on a target time of 16.02 seconds, turns a result into championship points so it can be added to the other nine events. See Millennium Standard targets for each event for the details.
Our Speed Cards drill uses this exact formula, and complete-deck runs are comparable with each other. Runs with fewer than 52 cards are for practice and are not comparable with full decks. If you are still building your system, start with how to memorize a deck of cards. For the rules behind other events, see the memory championship scoring rules.
