Exhibit

Longest runs.

Look down a shuffled deck for the longest stretch of a single color. Usually it is five or six cards. This room holds the shuffles where it reached fifteen or more.

What is ranked

The longest run of consecutive cards of the same color, red or black, anywhere in the 52-card order. Ties are ordered by archive number, oldest first.

How rare

Of all possible decks, about one in 10,769 contains a run of 15 or more. The exact distribution comes from a dynamic program over every arrangement of 26 red and 26 black cards.

The record

20 red

Shuffle #8,262,620, recorded August 4, 2025. 1,323 shuffles have qualified so far.

RankShuffleRun lengthShuffledEra
301#9,377,25416 redAugust 18, 20252025 engine
302#9,463,95816 blackAugust 19, 20252025 engine
303#9,497,53216 redAugust 19, 20252025 engine
304#9,499,57816 blackAugust 19, 20252025 engine
305#9,507,82416 blackAugust 19, 20252025 engine
306#9,566,60916 blackAugust 20, 20252025 engine
307#9,583,54116 redAugust 20, 20252025 engine
308#9,603,40616 redAugust 20, 20252025 engine
309#9,641,08116 redAugust 21, 20252025 engine
310#9,650,37016 redAugust 21, 20252025 engine
311#9,673,64116 redAugust 21, 20252025 engine
312#9,748,49816 redAugust 22, 20252025 engine
313#9,772,74316 redAugust 22, 20252025 engine
314#9,850,45016 redAugust 23, 20252025 engine
315#9,873,62916 redAugust 24, 20252025 engine
316#10,087,45116 redAugust 26, 20252025 engine
317#10,095,69716 redAugust 26, 20252025 engine
318#10,095,83516 redAugust 26, 20252025 engine
319#10,118,40616 redAugust 26, 20252025 engine
320#10,128,70216 redAugust 27, 20252025 engine
321#10,136,79416 redAugust 27, 20252025 engine
322#10,142,43616 redAugust 27, 20252025 engine
323#10,201,77716 blackAugust 27, 20252025 engine
324#10,211,48816 blackAugust 28, 20252025 engine
325#10,452,76716 redAugust 30, 20252025 engine
326#10,461,09116 blackAugust 30, 20252025 engine
327#10,462,90916 redAugust 30, 20252025 engine
328#10,581,24716 redSeptember 1, 20252025 engine
329#10,620,35116 blackSeptember 1, 20252025 engine
330#10,660,69316 blackSeptember 2, 20252025 engine
331#10,697,26816 blackSeptember 2, 20252025 engine
332#10,730,54016 redSeptember 3, 20252025 engine
333#10,764,25216 blackSeptember 3, 20252025 engine
334#10,814,76916 redSeptember 4, 20252025 engine
335#10,874,75416 redSeptember 4, 20252025 engine
336#10,944,69216 blackSeptember 5, 20252025 engine
337#10,947,10616 blackSeptember 5, 20252025 engine
338#10,953,39016 redSeptember 5, 20252025 engine
339#11,028,58216 blackSeptember 6, 20252025 engine
340#11,145,79516 blackSeptember 8, 20252025 engine
341#11,214,81116 redSeptember 8, 20252025 engine
342#11,294,35116 redSeptember 14, 20252025 engine
343#11,298,74416 redSeptember 14, 20252025 engine
344#11,357,17616 redSeptember 15, 20252025 engine
345#11,419,96816 blackSeptember 16, 20252025 engine
346#11,450,66116 redSeptember 16, 20252025 engine
347#11,537,35116 redSeptember 17, 20252025 engine
348#11,564,41716 blackSeptember 18, 20252025 engine
349#11,690,14316 blackSeptember 19, 20252025 engine
350#11,731,03316 blackSeptember 20, 20252025 engine
351#11,737,57016 redSeptember 20, 20252025 engine
352#11,759,53016 redSeptember 20, 20252025 engine
353#11,774,46116 redSeptember 20, 20252025 engine
354#11,828,51016 blackSeptember 21, 20252025 engine
355#11,907,27316 blackSeptember 22, 20252025 engine
356#11,936,19516 redSeptember 22, 20252025 engine
357#12,051,67316 blackSeptember 23, 20252025 engine
358#12,063,61316 blackSeptember 23, 20252025 engine
359#12,074,00216 redSeptember 24, 20252025 engine
360#12,123,97216 redSeptember 24, 20252025 engine
361#12,136,89816 blackSeptember 24, 20252025 engine
362#12,159,24416 redSeptember 25, 20252025 engine
363#12,184,17116 blackSeptember 25, 20252025 engine
364#12,224,48916 blackSeptember 25, 20252025 engine
365#12,229,82116 blackSeptember 25, 20252025 engine
366#12,243,00216 redSeptember 26, 20252025 engine
367#12,258,12816 redSeptember 26, 20252025 engine
368#12,354,28516 blackAugust 28, 2026this site
369#12,396,22316 redAugust 29, 2026this site
370#12,433,76116 blackAugust 29, 2026this site
371#12,516,38216 blackAugust 30, 2026this site
372#12,536,44116 redAugust 31, 2026this site
373#12,553,55216 blackAugust 31, 2026this site
374#12,701,19216 redSeptember 1, 2026this site
375#12,764,08016 redSeptember 2, 2026this site
376#12,898,38416 blackSeptember 4, 2026this site
377#12,952,15716 blackSeptember 4, 2026this site
378#12,964,89416 blackSeptember 4, 2026this site
379#12,980,25316 blackSeptember 5, 2026this site
380#13,011,62516 redSeptember 5, 2026this site
381#13,033,28716 blackSeptember 5, 2026this site
382#13,051,27816 redSeptember 5, 2026this site
383#13,058,20216 redSeptember 6, 2026this site
384#13,119,47016 redSeptember 6, 2026this site
385#13,180,74916 blackSeptember 7, 2026this site
386#13,247,67716 redSeptember 8, 2026this site
387#13,247,69416 blackSeptember 8, 2026this site
388#13,305,04416 redSeptember 8, 2026this site
389#13,341,38716 blackSeptember 9, 2026this site
390#13,412,76316 redSeptember 10, 2026this site
391#13,416,81616 redSeptember 10, 2026this site
392#13,450,82316 blackSeptember 10, 2026this site
393#13,453,91816 blackSeptember 10, 2026this site
394#13,453,94016 blackSeptember 10, 2026this site
395#13,550,18316 redSeptember 11, 2026this site
396#13,621,09416 blackSeptember 12, 2026this site
397#13,704,79316 redSeptember 13, 2026this site
398#13,707,10716 blackSeptember 13, 2026this site
399#13,849,39816 redSeptember 15, 2026this site
400#13,874,15116 redSeptember 15, 2026this site

A run this long is not a sign of a bad shuffle. The GSR model page explains why a well-mixed deck still produces streaks, and how often.