| The Syllabary Cipher – Part 3 | 1,184 | May 30, 2023, 11:22 p.m. |
| The Syllabary Cipher – Part 5 | 1,184 | May 30, 2023, 10:59 p.m. |
| The Syllabary Cipher – Part 4 | 1,184 | May 30, 2023, 10:57 p.m. |
| The Josse Challenge – Part 3 | 1,613 | March 31, 2023, 6:21 p.m. |
| The Josse Challenge – Part 2 | 1,321 | March 31, 2023, 6:19 p.m. |
| The Josse Challenge – Part 1 | 1,286 | March 31, 2023, 6:17 p.m. |
| The Syllabary Cipher – Part 1 | 102 | Dec. 16, 2022, 10:58 p.m. |
| A Secret Message from Castle Mansfeld | 100 | June 17, 2022, 4:25 p.m. |
| Trifid Cipher | 100 | June 17, 2022, 12:52 a.m. |
| Image Noise | 100 | June 16, 2022, 10:35 p.m. |
| Grille Cipher | 100 | June 16, 2022, 9:58 p.m. |
| The Last Note | 100 | June 4, 2022, 10:20 a.m. |
| Modular Sequences | 100 | June 3, 2022, 10:42 p.m. |
| Cryptanalysis Hacking Puzzles — Part 2 | 100 | June 3, 2022, 9:45 p.m. |
| The SZ42 Challenge — Part 13 | 1,178 | June 3, 2022, 8:30 p.m. |
| Alberti Challenge — Part 1 | 102 | May 27, 2022, 10:30 p.m. |
| Alberti Challenge — Part 2 | 1,433 | May 27, 2022, 10:27 p.m. |
| Modified Vigenère Cipher | 1,228 | May 7, 2022, 4:30 p.m. |
| The SZ42 Challenge — Part 12 | 1,238 | Jan. 5, 2022, 12:01 a.m. |
| Weakened ElsieFour — Part 2 | 1,109 | Jan. 3, 2022, 2:39 p.m. |
| Weakened ElsieFour — Part 1 | 1,109 | Jan. 3, 2022, 12:24 p.m. |
| The Heavy T52 Sturgeon Challenge — Part 2 | 13,784 | Dec. 20, 2021, 2:14 a.m. |
| The Heavy T52 Sturgeon Challenge — Part 9 | 13,987 | Nov. 1, 2021, 9:53 a.m. |
| The Heavy T52 Sturgeon Challenge — Part 7 | 13,980 | Oct. 31, 2021, 12:29 p.m. |
| The Heavy T52 Sturgeon Challenge — Part 6 | 13,980 | Oct. 31, 2021, 12:23 p.m. |
| The Heavy T52 Sturgeon Challenge — Part 5 | 13,978 | Oct. 31, 2021, 12:17 p.m. |
| SIGABA CSP-2900 — Part 1 | 1,725 | Aug. 3, 2021, 9:42 a.m. |
| SIGABA CSP-2900 — Part 2 | 1,725 | Aug. 3, 2021, 6:31 a.m. |
| SIGABA CSP-2900 — Part 3 | 19,236 | Aug. 2, 2021, 1:04 p.m. |
| Number Sequence — Part 10 | 100 | June 11, 2021, 9:26 p.m. |
| Number Sequence — Part 8 | 100 | June 11, 2021, 8:44 p.m. |
| Polyhomophonic Substitution — Part 1 | 100 | June 11, 2021, 3:40 p.m. |
| Find the right route — Part 1 | 100 | June 11, 2021, 3:27 p.m. |
| SIGABA CSP-889 — Part 2 | 1,613 | June 5, 2021, 2:08 p.m. |
| SIGABA CSP-889 — Part 1 | 1,725 | June 3, 2021, 10:50 p.m. |
| SIGABA CSP-889 — Part 3 | 20,000 | June 1, 2021, 9:12 p.m. |
| The SZ42 Challenge — Part 9 | 1,200 | May 27, 2021, 9:20 p.m. |
| Wheatstone Cryptograph — Part 2 | 1,547 | May 27, 2021, 9:18 p.m. |
| Wheatstone Cryptograph — Part 1 | 125 | April 25, 2021, 4:37 p.m. |
| The SZ42 Challenge — Part 11 | 1,385 | Feb. 19, 2021, 2:58 p.m. |
| The SZ42 Challenge — Part 10 | 1,660 | Feb. 2, 2021, 7:40 p.m. |
| The Heavy T52 Sturgeon Challenge — Part 3 | 14,125 | Dec. 31, 2020, 12:43 p.m. |
| The SZ42 Challenge — Part 8 | 1,373 | Nov. 21, 2020, 5:53 p.m. |
| The SZ42 Challenge — Part 7 | 1,353 | Nov. 21, 2020, 5:18 p.m. |
| The SZ42 Challenge — Part 6 | 1,286 | Nov. 21, 2020, 5:07 p.m. |
| RSA Factoring Challenge: RSA-240 | 0 | Sept. 6, 2020, 12:15 p.m. |
| RSA Factoring Challenge: RSA-250 | 0 | Sept. 6, 2020, 12:14 p.m. |
| RSA Factoring Challenge: RSA-232 | 0 | Sept. 6, 2020, 12:13 p.m. |
| RSA Factoring Challenge: RSA-220 | 0 | Sept. 6, 2020, 12:12 p.m. |
| RSA Factoring Challenge: RSA-230 | 0 | Sept. 6, 2020, 12:11 p.m. |
| RSA Factoring Challenge: RSA-210 | 0 | Sept. 6, 2020, 12:09 p.m. |
| The SZ42 Challenge — Part 5 | 2,000 | Sept. 3, 2020, 4:19 p.m. |
| The SZ42 Challenge — Part 4 | 2,000 | Aug. 30, 2020, 5:19 p.m. |
| The SZ42 Challenge — Part 3 | 1,576 | Aug. 21, 2020, 9:02 p.m. |
| The SZ42 Challenge — Part 2 | 2,000 | Aug. 5, 2020, 5:05 p.m. |
| The SZ42 Challenge — Part 1 | 1,547 | July 29, 2020, 10:48 a.m. |
| Polyhomophonic Substitution — Part 3 | 1,310 | May 14, 2020, 11:52 p.m. |
| Polyhomophonic Substitution — Part 2 | 1,290 | May 14, 2020, 11:02 p.m. |
| The Heavy T52 Sturgeon Challenge — Part 4 | 16,705 | May 2, 2020, 11:16 a.m. |
| The Heavy T52 Sturgeon Challenge — Part 1 | 14,576 | April 25, 2020, 7:03 p.m. |
| The LoRa Cipher: Logic Randomness — Part 1 | 1,330 | March 21, 2020, 9:04 p.m. |
| Polyphonic Substitution Cipher — Part 2 | 1,824 | Jan. 16, 2020, 12:47 a.m. |
| Polyphonic Substitution Cipher — Part 1 | 1,725 | Nov. 23, 2019, 5:29 p.m. |
| Cipher ID — Part 1 | 1,660 | Nov. 22, 2019, 11:30 p.m. |
| A Cloaked Substitution Cipher — Part 1 | 1,357 | Sept. 14, 2019, 4:21 p.m. |
| A Cloaked Substitution Cipher — Part 2 | 1,385 | Sept. 14, 2019, 1:17 p.m. |
| Homophonic Encryption — Part 2 | 1,725 | May 10, 2019, 10:02 p.m. |
| Homophonic Encryption — Part 3 | 2,000 | May 9, 2019, 8:51 p.m. |
| Homophonic Encryption — Part 4 | 2,000 | May 9, 2019, 8:48 p.m. |
| Homophonic Encryption — Part 1 | 1,660 | May 7, 2019, 10:40 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | Feb. 23, 2019, 10:05 p.m. |
| Autokey Cipher | 101 | Feb. 23, 2019, 8:06 p.m. |
| Monoalphabetic Substitution with Nostradamus Flavor | 2,000 | Feb. 16, 2019, 9:43 p.m. |
| Handycipher made in love — Part 1 | 2,000 | Feb. 16, 2019, 9:36 p.m. |
| Akelarre Part 1 | 1,088 | Jan. 8, 2019, 9:50 p.m. |
| Breaking a Filter Generator | 1,330 | Oct. 27, 2018, 2:15 a.m. |
| Kaskade-S/T — Part 6 (RansomKaskade Part 1) | 1,156 | July 8, 2018, 10:27 p.m. |
| Fastest in the West | 1,367 | July 4, 2018, 11:19 p.m. |
| Summer Job | 1,367 | July 4, 2018, 10:04 p.m. |
| Advent-Challenge — Part 1 | 103 | Jan. 13, 2018, 6:40 p.m. |
| Spirale — Part 3 | 1,129 | Aug. 21, 2017, 9:46 p.m. |
| Spirale — Part 2 | 1,129 | Aug. 21, 2017, 9:06 p.m. |
| Spirale — Part 1 | 1,129 | Aug. 21, 2017, 8:56 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,092 | Aug. 12, 2017, 6:57 p.m. |
| Keyshanc — Part 2 | 1,099 | Aug. 6, 2017, 8:46 p.m. |
| Keyshanc — Part 1 | 1,099 | Aug. 6, 2017, 7:44 p.m. |
| Unusual encryption using a diophantine equation | 1,095 | Aug. 6, 2017, 12:43 a.m. |
| A really long number sequence | 1,096 | Aug. 5, 2017, 10:44 p.m. |
| RSA: Two different keys — same ciphertext | 1,095 | Aug. 5, 2017, 4:10 p.m. |
| RSA with Special d | 13,248 | Aug. 5, 2017, 12:08 a.m. |
| Alice's Birthday Party (Part 2) | 1,092 | Aug. 1, 2017, 8:21 p.m. |
| Alice's Birthday Party (Part 1) | 1,092 | Aug. 1, 2017, 8:16 p.m. |
| Pigpen with a twist — Part 3 | 1,096 | Aug. 1, 2017, 12:17 p.m. |
| Pigpen with a twist — Part 2 | 1,096 | Aug. 1, 2017, 11:45 a.m. |
| ASAC — A Strong(er) ADFGVX Cipher — Part 2 | 1,155 | Aug. 1, 2017, 12:01 a.m. |
| ASAC — A Strong(er) ADFGVX Cipher — Part 1 | 1,155 | July 31, 2017, 9:27 p.m. |
| Monoalphabetic substitution with camouflage — Part 4 | 100 | July 30, 2017, 7:23 p.m. |
| Broadcasting and low exponent — RSA Attack | 1,095 | July 30, 2017, 1:25 p.m. |
| Partial Key Exposure with RSA — Part 1 | 1,098 | July 30, 2017, 12:01 a.m. |
| Hybrid Encryption I | 1,092 | July 29, 2017, 11:16 p.m. |
| Zodiac Cipher | 100 | July 29, 2017, 3:29 p.m. |
| Monoalphabetic substitution with camouflage — Part 3 | 1,097 | July 29, 2017, 12:12 p.m. |
| Monoalphabetic substitution with camouflage — Part 2 | 1,097 | July 29, 2017, 12:08 p.m. |
| Monoalphabetic substitution with camouflage — Part 1 | 100 | July 29, 2017, 11:54 a.m. |
| Monoalphabetic Substitution with Camouflage — Part 5 | 1,098 | July 29, 2017, 11:30 a.m. |
| ORYX Stream Cipher — Part 3 (revised) | 1,106 | June 28, 2017, 3:20 p.m. |
| ORYX Stream Cipher — Part 4b | 13,594 | June 27, 2017, 11:31 a.m. |
| ORYX Stream Cipher — Part 4a | 1,113 | June 26, 2017, 8:18 p.m. |
| ORYX Stream Cipher Part II | 1,092 | June 24, 2017, 10:45 p.m. |
| ORYX Stream Cipher Part I | 1,092 | June 24, 2017, 9:53 p.m. |
| CMEA 1 | 1,093 | June 22, 2017, 11:03 p.m. |
| CMEA 2 | 13,265 | June 22, 2017, 9:57 p.m. |
| Weakened Granit — Part 1 | 100 | June 17, 2017, 9:50 p.m. |
| Sigaba Part 2 | 13,258 | June 8, 2017, 6:55 a.m. |
| Sigaba Part 1 | 1,093 | June 6, 2017, 11:14 p.m. |
| Handycipher — Part 9 | 14,906 | May 31, 2017, 11 a.m. |
| Extended Handycipher — Part 3 | 1,126 | May 31, 2017, 10:24 a.m. |
| Extended Handycipher — Part 1 | 1,126 | May 31, 2017, 10:23 a.m. |
| Extended Handycipher — Part 2 | 1,126 | May 31, 2017, 10:18 a.m. |
| Weakened Handycipher — Part 4 | 1,161 | May 30, 2017, 4 p.m. |
| Extended Handycipher — Part 6 | 14,274 | May 30, 2017, 3:01 p.m. |
| Weakened Handycipher — Part 5 | 1,161 | May 29, 2017, 9:15 p.m. |
| Weakened Handycipher — Part 6 | 1,161 | May 29, 2017, 1:02 a.m. |
| Extended Handycipher — Part 5 | 14,276 | May 29, 2017, 12:37 a.m. |
| Extended Handycipher — Part 4 | 14,276 | May 29, 2017, 12:30 a.m. |
| Handycipher — Part 4 | 14,276 | May 29, 2017, 12:06 a.m. |
| Handycipher — Part 5 | 14,276 | May 28, 2017, 11:56 p.m. |
| Handycipher — Part 6 | 14,276 | May 28, 2017, 11:48 p.m. |
| Handycipher — Part 7 | 14,917 | May 28, 2017, 11:43 p.m. |
| Handycipher — Part 8 | 14,917 | May 28, 2017, 11:32 p.m. |
| Weakened Handycipher — Part 1 | 1,128 | May 28, 2017, 10:01 p.m. |
| Weakened Handycipher — Part 3 | 1,128 | May 27, 2017, 3:40 a.m. |
| Weakened Handycipher — Part 2 | 1,128 | May 27, 2017, 3:33 a.m. |
| Handycipher — Part 3 | 13,775 | May 27, 2017, 2 a.m. |
| Handycipher — Part 2 | 1,125 | May 27, 2017, 1:48 a.m. |
| Handycipher — Part 1 | 1,125 | May 27, 2017, 1:43 a.m. |
| M-138 — Part 4 | 1,122 | May 24, 2017, 9:45 a.m. |
| M-138 — Part 3 | 1,240 | March 21, 2015, 2:09 p.m. |
| M-138 — Part 2 | 1,240 | March 21, 2015, 1:53 a.m. |
| M-138 — Part 1 | 101 | March 21, 2015, 1:09 a.m. |
| Factorization Cipher — Part 3 | 1,117 | Nov. 13, 2014, 12:11 a.m. |
| Factorization Cipher — Part 2 | 1,116 | Nov. 12, 2014, 12:59 a.m. |
| Purple 1 | 1,110 | May 2, 2014, 2:40 a.m. |
| Typex — Part 2 | 1,155 | April 26, 2014, 11:08 a.m. |
| Typex — Part 1 | 1,151 | April 26, 2014, 9:59 a.m. |
| Spanish Strip Cipher — Part 1 | 1,523 | April 3, 2014, 10:57 p.m. |
| Spanish Strip Cipher — Part 2 | 1,660 | March 31, 2014, 1:04 a.m. |
| Monoalphabetic Substitution | 100 | Dec. 12, 2013, 5:02 p.m. |
| Classical Ciphers^3 | 100 | Dec. 12, 2013, 3:51 p.m. |
| Notes of an Italian Soldier | 800 | Dec. 12, 2013, 3:07 p.m. |
| AES key — encoded in the machine readable zone of a European ePassport | 1,131 | Dec. 11, 2013, 12:14 a.m. |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 1,114 | Dec. 10, 2013, 3:47 a.m. |
| Cracking SHA1-Hashed Passwords | 1,119 | Dec. 10, 2013, 1:03 a.m. |
| Kaskade-S/T — Part 5 | 1,120 | Dec. 9, 2013, 3 a.m. |
| How do you become a big cryptographer? | 100 | Dec. 4, 2013, 12:07 a.m. |
| Beaver Code | 100 | Dec. 3, 2013, 11:38 p.m. |
| Nils away on travel | 101 | Dec. 3, 2013, 5:21 p.m. |
| From Russia with Love | 101 | Dec. 3, 2013, 5:13 p.m. |
| Multilingual Monoalphabetic Substitution | 100 | Dec. 3, 2013, 3:30 a.m. |
| Double Column Transposition | 11,000 | Nov. 26, 2013, 5:23 p.m. |
| Cascading Encryption — Part 3/3 | 1,190 | Oct. 7, 2013, 4:33 a.m. |
| Pigpen with a twist — Part 1 | 100 | Sept. 22, 2013, 12:10 a.m. |
| Cascading Encryption — Part 2/3 | 1,193 | Sept. 21, 2013, 1:27 a.m. |
| Modified Caesar Cipher | 100 | Sept. 9, 2013, 4:17 p.m. |
| Number Sequence — Part 3 | 100 | Sept. 4, 2013, 1:04 a.m. |
| Number Sequence — Part 4 | 100 | Sept. 4, 2013, 1:03 a.m. |
| ¿No Hablas Español? No problemo! | 100 | Sept. 4, 2013, 12:59 a.m. |
| Double Columnar Transposition | 100 | Sept. 4, 2013, 12:51 a.m. |
| One-Time Pad with Flaws | 100 | Sept. 4, 2013, 12:19 a.m. |
| Molehunt (Part 3/3) | 1,117 | Sept. 3, 2013, 11:08 p.m. |
| Molehunt (Part 2/3) | 100 | Sept. 3, 2013, 7:01 p.m. |
| Molehunt (Part 1/3) | 100 | Sept. 3, 2013, 5:09 p.m. |
| Number Sequence | 100 | Sept. 3, 2013, 5 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | Sept. 1, 2013, 11:48 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | Sept. 1, 2013, 3:05 a.m. |
| Caesar Encryption | 100 | Sept. 1, 2013, 2:45 a.m. |
| Ku Klux Klan | 1,000 | Aug. 30, 2013, 4:53 p.m. |
| Factorization Cipher — Part 1 | 100 | Aug. 25, 2013, 5:13 p.m. |
| Kaskade-S/T — Part 3 | 1,122 | Aug. 25, 2013, 12:04 a.m. |
| Kaskade-S/T — Part 2 | 1,122 | Aug. 23, 2013, 10:15 p.m. |
| Kaskade-S/T — Part 1 | 100 | Aug. 23, 2013, 5:29 p.m. |
| Letter to the Templars — Part 3 | 1,164 | Aug. 21, 2013, 12:34 a.m. |
| Letter to the Templars — Part 2 | 100 | Aug. 21, 2013, 12:03 a.m. |
| Letter to the Templars — Part 1 | 100 | Aug. 20, 2013, 11:52 p.m. |
| Number Sequence — Part 2 | 100 | Aug. 20, 2013, 11:36 p.m. |
| Original Caesar Cipher | 100 | Aug. 20, 2013, 11:31 p.m. |
| ADFGVX — Part 1 | 100 | Aug. 20, 2013, 11:05 p.m. |
| ADFGVX — Part 2 | 100 | Aug. 20, 2013, 10:46 p.m. |
| Cascading Encryption — Part 1/3 | 100 | Aug. 19, 2013, 11:46 p.m. |
| Playfair Encryption | 100 | Aug. 18, 2013, 12:47 a.m. |
| Playfair with hints about the grid | 100 | Aug. 18, 2013, 12:41 a.m. |
| Turing Bombe Enigma I | 100 | Aug. 17, 2013, 1:59 a.m. |
| Recycled One-Time Pad | 100 | Aug. 17, 2013, 1:37 a.m. |
| Enigma Messages | 100 | Aug. 16, 2013, 10:49 p.m. |
| Enigma Part 2 | 1,118 | July 16, 2013, 9:30 p.m. |