| Number Sequence | 4353 | 100 | Oct. 14, 2010 |
| Original Caesar Cipher | 3069 | 100 | Dec. 15, 2010 |
| Number Sequence — Part 2 | 2143 | 100 | July 11, 2011 |
| Caesar Encryption | 1467 | 100 | Oct. 21, 2010 |
| Beaver Code | 1214 | 100 | Aug. 13, 2012 |
| Letter to the Templars — Part 1 | 1044 | 100 | July 16, 2012 |
| Number Sequence — Part 3 | 1027 | 100 | March 30, 2012 |
| A hidden word | 858 | 100 | Jan. 6, 2013 |
| Number Sequence — Part 4 | 849 | 100 | April 18, 2012 |
| Letter to the Templars — Part 2 | 839 | 100 | July 30, 2012 |
| Letter to the Templars — Part 3 | 715 | 1081 | Oct. 9, 2012 |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 602 | 100 | Sept. 9, 2011 |
| Cracking SHA1-Hashed Passwords | 571 | 1078 | April 4, 2011 |
| Monoalphabetic Substitution | 556 | 100 | Oct. 14, 2010 |
| Factorization Cipher — Part 1 | 513 | 100 | Oct. 17, 2011 |
| Grille Cipher | 499 | 100 | Oct. 14, 2011 |
| Advent-Challenge — Part 1 | 498 | 100 | Dec. 8, 2017 |
| Number Sequence — Part 8 | 405 | 100 | Sept. 14, 2015 |
| A modified homophonic cipher with reduced alphabets — Part 1 | 398 | 100 | Oct. 21, 2010 |
| A modified homophonic cipher with reduced alphabets — Part 2 | 343 | 100 | Oct. 21, 2010 |
| One-Time Pad with Flaws | 315 | 100 | Nov. 12, 2010 |
| Alice's Birthday Party (Part 1) | 304 | 1077 | Oct. 14, 2010 |
| Snow White and the seven dwarfs | 295 | 100 | April 20, 2013 |
| From Russia with Love | 293 | 100 | Sept. 4, 2013 |
| Alice's Birthday Party (Part 2) | 292 | 1077 | Oct. 14, 2010 |
| Broadcasting and low exponent — RSA Attack | 239 | 1079 | July 22, 2011 |
| Modified Caesar Cipher | 233 | 100 | Sept. 2, 2011 |
| How do you become a big cryptographer? | 230 | 100 | May 28, 2012 |
| M-138 — Part 1 | 224 | 100 | Dec. 24, 2014 |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 205 | 1077 | Oct. 14, 2010 |
| Cryptanalysis Hacking Puzzles — Part 2 | 205 | 100 | Jan. 9, 2019 |
| Not-so-Secret Message from Malawi — Part I (RSA) | 203 | 1077 | Oct. 14, 2010 |
| Reserve Hand Procedure — Part 1 | 195 | 100 | March 6, 2013 |
| Classical Ciphers^3 | 188 | 100 | Oct. 14, 2010 |
| Autokey Cipher | 188 | 100 | Sept. 25, 2018 |
| The Syllabary Cipher – Part 1 | 185 | 100 | Oct. 28, 2022 |
| Letter from the Alleged Countess Julie von Ortenburg | 181 | 100 | Oct. 14, 2010 |
| Enigma Messages with Repeated Letters — Part 1 | 179 | 100 | Sept. 26, 2013 |
| Hybrid Encryption I | 178 | 1077 | Nov. 2, 2010 |
| Nils away on travel | 175 | 100 | Aug. 8, 2013 |
| ¿No Hablas Español? No problemo! | 168 | 100 | April 18, 2012 |
| Number Sequence — Part 6 | 163 | 100 | March 23, 2015 |
| Image Noise | 161 | 100 | Nov. 20, 2015 |
| Molehunt (Part 1/3) | 159 | 100 | Oct. 23, 2010 |
| RSA: Two different keys — same ciphertext | 157 | 1079 | Aug. 15, 2011 |
| Pigpen with a twist — Part 1 | 156 | 100 | Sept. 5, 2011 |
| The Book Code: A Challenge for Bookworms | 153 | 100 | March 21, 2012 |
| Molehunt (Part 2/3) | 150 | 100 | Oct. 23, 2010 |
| Factorization Cipher — Part 2 | 150 | 1079 | Dec. 1, 2011 |
| M-138 — Part 2 | 138 | 1086 | Dec. 24, 2014 |
| Enigma Part 1 | 132 | 1077 | Oct. 14, 2010 |
| A Secret Message from Castle Mansfeld | 131 | 100 | Oct. 14, 2010 |
| Alberti Challenge — Part 1 | 131 | 100 | March 26, 2022 |
| Playfair Encryption | 128 | 100 | Dec. 22, 2010 |
| Trifid Cipher | 128 | 100 | Oct. 28, 2013 |
| ADFGVX — Part 2 | 126 | 100 | Aug. 15, 2011 |
| ADFGVX — Part 1 | 121 | 100 | Aug. 15, 2011 |
| A really long number sequence | 120 | 1079 | Sept. 5, 2011 |
| Number Sequence — Part 9 | 120 | 100 | Nov. 16, 2017 |
| Playfair with hints about the grid | 119 | 100 | Jan. 16, 2013 |
| Double Columnar Transposition | 118 | 100 | Oct. 12, 2011 |
| Number Sequence — Part 10 | 118 | 100 | April 18, 2018 |
| A hidden word — Part 2 | 113 | 100 | April 16, 2015 |
| Enigma Combinatorics | 107 | 100 | Nov. 12, 2010 |
| Kaskade-S/T — Part 1 | 107 | 100 | March 4, 2011 |
| Hill Cipher with Sudoku Key | 107 | 100 | Sept. 4, 2013 |
| Number Sequence — Part 5 | 104 | 100 | April 18, 2012 |
| Wheatstone Cryptograph — Part 1 | 102 | 100 | April 21, 2021 |
| Zodiac Cipher | 101 | 100 | Oct. 14, 2010 |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 1 | 100 | 100 | April 7, 2011 |
| ECDH-Key Exchange for Beginners | 100 | 100 | Feb. 24, 2012 |
| The Last Note | 99 | 100 | Sept. 22, 2014 |
| Factorization Cipher — Part 3 | 97 | 1079 | Jan. 6, 2012 |
| Number Sequence — Part 7 | 97 | 100 | March 23, 2015 |
| Enigma Part 2 | 91 | 1077 | Oct. 14, 2010 |
| Heartbleed — Part 1 | 90 | 0 | Aug. 28, 2014 |
| Find the right route — Part 1 | 90 | 100 | Oct. 27, 2020 |
| Partial Key Exposure with RSA — Part 1 | 88 | 1080 | Feb. 11, 2012 |
| Enigma Messages with Repeated Letters — Part 2 | 86 | 100 | Oct. 28, 2013 |
| Enigma Messages with Repeated Letters — Part 3 | 86 | 100 | March 5, 2014 |
| Molehunt (Part 3/3) | 82 | 1077 | Oct. 23, 2010 |
| Enigma Messages | 82 | 100 | Jan. 23, 2013 |
| Enigma Messages with Repeated Letters — Part 5 | 82 | 100 | March 5, 2014 |
| AES key — encoded in the machine readable zone of a European ePassport | 81 | 1079 | Jan. 16, 2012 |
| ORYX Stream Cipher Part I | 80 | 1077 | Oct. 14, 2010 |
| Multilingual Monoalphabetic Substitution | 79 | 100 | Jan. 30, 2013 |
| Modular Sequences | 79 | 100 | Sept. 25, 2018 |
| Enigma Messages with Repeated Letters — Part 4 | 78 | 100 | March 5, 2014 |
| Smartcard RSA | 76 | 1077 | Oct. 25, 2010 |
| BCR code (Book-Caesar-RSA) | 75 | 1081 | Sept. 12, 2012 |
| Turing Bombe Enigma I | 73 | 100 | Oct. 17, 2011 |
| Cascading Encryption — Part 1/3 | 73 | 100 | Jan. 25, 2013 |
| Unusual encryption using a diophantine equation | 69 | 1079 | Sept. 2, 2011 |
| Recycled One-Time Pad | 69 | 100 | Nov. 20, 2012 |
| Monoalphabetic substitution with camouflage — Part 1 | 66 | 100 | Oct. 27, 2011 |
| RSA Factoring Challenge: RSA-704 | 66 | 0 | July 31, 2013 |
| M-138 — Part 3 | 65 | 1086 | Dec. 24, 2014 |
| RSA Factoring Challenge: RSA-210 | 62 | 0 | Feb. 7, 2012 |
| The Einstein Enigma | 62 | 1097 | Feb. 7, 2018 |
| An Invisible Message | 61 | 100 | Oct. 17, 2011 |
| Merkle-Hellman Knapsack Challenge - Part 1 | 61 | 100 | Oct. 14, 2022 |
| Heartbleed — Part 2 | 60 | 0 | Aug. 28, 2014 |
| News from Castle Mansfeld | 59 | 100 | Nov. 13, 2015 |
| Summer Job | 57 | 1098 | June 12, 2018 |
| Lightweight Introduction to Lattices — Part 1 | 56 | 100 | May 16, 2020 |
| Advent-Challenge — Part 2 | 55 | 1096 | Dec. 16, 2017 |
| Monoalphabetic substitution with camouflage — Part 2 | 54 | 1079 | Dec. 7, 2011 |
| New Year's Greetings — Part 1 | 54 | 100 | March 21, 2016 |
| Kaskade-S/T — Part 2 | 53 | 1078 | March 4, 2011 |
| Polyhomophonic Substitution — Part 1 | 53 | 100 | March 22, 2020 |
| Unconcealed RSA messages | 52 | 1079 | Nov. 2, 2011 |
| Monoalphabetic substitution with camouflage — Part 4 | 51 | 100 | Dec. 21, 2011 |
| Strange Message from Thessaloniki | 51 | 100 | Dec. 10, 2012 |
| Double Column Transposition — Part 4 | 51 | 1084 | May 19, 2014 |
| Monoalphabetic substitution with camouflage — Part 3 | 50 | 1079 | Dec. 7, 2011 |
| Keyshanc — Part 1 | 50 | 1080 | May 21, 2012 |
| Lunchtime Attack on the Fully Homomorphic Encryption Scheme | 49 | 1078 | Jan. 14, 2011 |
| Weakened Granit — Part 1 | 49 | 100 | Sept. 24, 2015 |
| New Year's Greetings — Part 2 | 49 | 100 | March 21, 2016 |
| ORYX Stream Cipher Part II | 48 | 1077 | Oct. 14, 2010 |
| Double Column Transposition — Part 2 | 47 | 1084 | May 2, 2014 |
| New Year's Greetings — Part 3 | 47 | 100 | March 21, 2016 |
| Advent Challenge — Part 3 | 47 | 1096 | Dec. 22, 2017 |
| RSA Factoring Challenge: RSA-220 | 46 | 0 | Feb. 7, 2012 |
| CMEA 1 | 45 | 1077 | Dec. 6, 2010 |
| Advent Challenge — Part 4 | 45 | 1096 | Dec. 21, 2017 |
| New Year's Greetings — Part 4 | 44 | 100 | March 21, 2016 |
| Not-so-Secret Message from Malawi — Part II (ECC) | 43 | 1077 | Oct. 14, 2010 |
| Music Code — Part 1 | 43 | 100 | May 17, 2011 |
| Homophonic Encryption — Part 1 | 43 | 1104 | May 4, 2019 |
| Ku Klux Klan | 42 | Variable | Oct. 14, 2010 |
| Music Code — Part 2 | 42 | 1078 | May 17, 2011 |
| Pigpen with a twist — Part 2 | 42 | 1079 | Sept. 2, 2011 |
| Pigpen with a twist — Part 3 | 41 | 1079 | Sept. 2, 2011 |
| Keyshanc — Part 2 | 41 | 1080 | May 21, 2012 |
| An 'unhearable' message | 41 | 100 | June 5, 2012 |
| Double Column Transposition — Part 3 | 41 | 1084 | May 2, 2014 |
| Lightweight Introduction to Lattices — Part 2 | 40 | 100 | June 23, 2020 |
| RSA Factoring Challenge: RSA-230 | 39 | 0 | Feb. 7, 2012 |
| Fastest in the West | 38 | 1098 | June 12, 2018 |
| Homophonic Encryption — Part 2 | 38 | 1104 | May 8, 2019 |
| Monoalphabetic Substitution with Nostradamus Flavor | 37 | 1102 | Feb. 16, 2019 |
| Homophonic Encryption — Part 3 | 37 | 1104 | May 8, 2019 |
| Kaskade-S/T — Part 3 | 36 | 1078 | March 4, 2011 |
| Homophonic Encryption — Part 4 | 36 | 1104 | May 8, 2019 |
| Trendy Messenger | 35 | 1098 | June 12, 2018 |
| Lightweight Introduction to Lattices — Part 3 | 35 | 1113 | July 16, 2020 |
| Double Column Transposition — Part 1 | 34 | 1084 | April 4, 2014 |
| Lattice Part 1 | 33 | 1078 | March 11, 2011 |
| Monoalphabetic Substitution with Camouflage — Part 5 | 33 | 1080 | March 9, 2012 |
| Spanish Strip Cipher — Part 1 | 33 | 1084 | March 27, 2014 |
| Heartbleed — Part 3 | 33 | 0 | Aug. 28, 2014 |
| Cryptanalysis Hacking Puzzles — Part 1 | 33 | 100 | Oct. 26, 2018 |
| Find the right route — Part 2 | 33 | 100 | Dec. 19, 2020 |
| Spanish Strip Cipher — Part 2 | 32 | 1084 | March 27, 2014 |
| Find the right route — Part 3 | 32 | 100 | Dec. 26, 2020 |
| Typex — Part 1 | 31 | 1082 | Feb. 28, 2013 |
| ORYX Stream Cipher — Part 3 (revised) | 31 | 1082 | June 6, 2013 |
| M-138 — Part 4 | 31 | 1086 | Dec. 24, 2014 |
| CMEA 2 | 29 | 12990 | Dec. 6, 2010 |
| Polyhomophonic Substitution — Part 2 | 29 | 1110 | March 28, 2020 |
| AES ECB Wrong Encoding | 28 | 1096 | Dec. 16, 2017 |
| The LoRa Cipher: Logic Randomness — Part 1 | 28 | 1110 | Feb. 19, 2020 |
| RSA Factoring Challenge: RSA-232 | 27 | 0 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-240 | 27 | 0 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-250 | 26 | 0 | Feb. 7, 2012 |
| Handycipher made in love — Part 1 | 26 | 1102 | Feb. 16, 2019 |
| Typex — Part 2 | 25 | 1082 | April 3, 2013 |
| Polyphonic Substitution Cipher — Part 1 | 25 | 1108 | Nov. 21, 2019 |
| RSA with Special d | 24 | 12986 | Oct. 14, 2010 |
| The Syllabary Cipher – Part 2 | 24 | 1161 | Oct. 28, 2022 |
| Polyphonic Substitution Cipher — Part 2 | 23 | 1109 | Jan. 14, 2020 |
| Purple 1 | 21 | 1077 | Oct. 27, 2010 |
| A Cloaked Substitution Cipher — Part 1 | 21 | 1106 | Aug. 21, 2019 |
| Breaking a Filter Generator | 20 | 1100 | Sept. 25, 2018 |
| Handycipher made in love — Part 2 | 20 | 1104 | May 21, 2019 |
| The T52 Sturgeon Challenge — Part 1 | 20 | 1105 | July 13, 2019 |
| A Cloaked Substitution Cipher — Part 2 | 20 | 1106 | Aug. 25, 2019 |
| Cascading Encryption — Part 2/3 | 19 | 1082 | March 25, 2013 |
| Flawed Usage of a OTP Cipher by the BND | 19 | 1088 | Aug. 23, 2015 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 1 | 19 | 1090 | July 9, 2016 |
| The T52 Sturgeon Challenge — Part 2 | 19 | 1105 | July 22, 2019 |
| The Syllabary Cipher – Part 3 | 19 | 1161 | Oct. 28, 2022 |
| Sigaba Part 1 | 18 | 1077 | Oct. 14, 2010 |
| Polyhomophonic Substitution — Part 3 | 18 | 1111 | April 6, 2020 |
| The SZ42 Challenge — Part 1 | 18 | 1113 | July 22, 2020 |
| The SZ42 Challenge — Part 2 | 18 | 1114 | Aug. 5, 2020 |
| The Hutton Cipher – Part 1 | 18 | 1206 | May 2, 2023 |
| Cipher ID — Part 1 | 17 | 1107 | Nov. 19, 2019 |
| Concealed Messages — Vigenère's Night Sky | 16 | 0 | May 1, 2012 |
| New Year's Greetings — Part 5 | 16 | 1089 | March 21, 2016 |
| The SZ42 Challenge — Part 3 | 16 | 1114 | Aug. 15, 2020 |
| The SZ42 Challenge — Part 4 | 16 | 1114 | Aug. 29, 2020 |
| The SZ42 Challenge — Part 5 | 16 | 1115 | Sept. 3, 2020 |
| Weakened Handycipher — Part 1 | 15 | 1087 | May 13, 2015 |
| The T52 Sturgeon Challenge — Part 3 | 15 | 1105 | July 22, 2019 |
| Merkle-Hellman Knapsack Challenge — Part 2 | 15 | 1160 | Oct. 14, 2022 |
| The Hutton Cipher – Part 2 | 15 | 1222 | June 5, 2023 |
| Weakened Handycipher — Part 3 | 14 | 1087 | May 13, 2015 |
| The SZ42 Challenge — Part 6 | 14 | 1115 | Oct. 2, 2020 |
| The SZ42 Challenge — Part 8 | 14 | 1116 | Oct. 31, 2020 |
| Wheatstone Cryptograph — Part 2 | 14 | 1123 | May 21, 2021 |
| Weakened Handycipher — Part 2 | 13 | 1087 | May 13, 2015 |
| The T52 Sturgeon Challenge — Part 4 | 13 | 1105 | July 22, 2019 |
| The SZ42 Challenge — Part 7 | 13 | 1116 | Oct. 27, 2020 |
| The SZ42 Challenge — Part 9 | 13 | 1118 | Dec. 19, 2020 |
| The Syllabary Cipher – Part 4 | 13 | 1161 | Oct. 28, 2022 |
| The Syllabary Cipher – Part 5 | 13 | 1161 | Oct. 28, 2022 |
| The Josse Challenge – Part 1 | 13 | 1180 | Feb. 10, 2023 |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 2 | 12 | 1078 | April 13, 2011 |
| Cascading Encryption — Part 3/3 | 12 | 1082 | March 29, 2013 |
| ORYX Stream Cipher — Part 4a | 12 | 1084 | April 14, 2014 |
| The Josse Challenge – Part 2 | 12 | 1184 | Feb. 25, 2023 |
| Hill Cipher | 11 | 1155 | Sept. 4, 2022 |
| The Josse Challenge – Part 3 | 11 | 1192 | March 27, 2023 |
| Akelarre Part 1 | 10 | 1077 | Nov. 24, 2010 |
| Kaskade-S/T — Part 5 | 10 | 1078 | May 5, 2011 |
| The T52 Sturgeon Challenge — Part 8 | 10 | 1105 | Aug. 10, 2019 |
| The SIGABA Challenge — Part 1 | 10 | 1110 | Feb. 29, 2020 |
| Modified Vigenère Cipher | 10 | 1136 | Jan. 24, 2022 |
| Double Column Transposition — Part 5 | 9 | 1085 | June 23, 2014 |
| Hilly — Part 1 | 9 | 1092 | Jan. 25, 2017 |
| The T52 Sturgeon Challenge — Part 11 | 9 | 1105 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 12 | 9 | 1105 | Aug. 10, 2019 |
| The SIGABA Challenge — Part 2 | 9 | 1110 | March 5, 2020 |
| The SZ42 Challenge — Part 12 | 9 | 1130 | Oct. 6, 2021 |
| Alberti Challenge — Part 2 | 9 | 1144 | May 14, 2022 |
| "The Road" — Part 1 | 8 | 1101 | Dec. 8, 2018 |
| The T52 Sturgeon Challenge — Part 9 | 8 | 1105 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 10 | 8 | 1105 | Aug. 10, 2019 |
| The SZ42 Challenge — Part 13 | 8 | 1130 | Oct. 6, 2021 |
| Handycipher — Part 2 | 7 | 1086 | March 3, 2015 |
| Spirale — Part 1 | 7 | 1088 | Aug. 23, 2015 |
| Spirale — Part 2 | 7 | 1088 | Aug. 23, 2015 |
| Holographic Encryption — Part 1 | 7 | 1093 | April 7, 2017 |
| The T52 Sturgeon Challenge — Part 5 | 7 | 1105 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 6 | 7 | 1105 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 7 | 7 | 1105 | Aug. 10, 2019 |
| The Heavy T52 Sturgeon Challenge — Part 7 | 7 | 13561 | April 23, 2020 |
| Handycipher — Part 3 | 6 | 13151 | March 3, 2015 |
| Kaskade-S/T — Part 6 (RansomKaskade Part 1) | 6 | 1094 | July 2, 2017 |
| Weakened ElsieFour — Part 1 | 6 | 1098 | April 28, 2018 |
| The SIGABA Challenge — Part 3 | 6 | 13545 | March 11, 2020 |
| The Heavy T52 Sturgeon Challenge — Part 4 | 6 | 13558 | April 15, 2020 |
| The Heavy T52 Sturgeon Challenge — Part 5 | 6 | 13560 | April 21, 2020 |
| Sigaba Part 2 | 5 | 12986 | Oct. 14, 2010 |
| Handycipher — Part 1 | 5 | 1086 | March 3, 2015 |
| Spirale — Part 3 | 5 | 1088 | Aug. 23, 2015 |
| Handycipher — Part 5 | 5 | 13222 | June 28, 2016 |
| Handycipher — Part 6 | 5 | 13222 | June 28, 2016 |
| Weakened Handycipher — Part 4 | 5 | 1090 | June 28, 2016 |
| Weakened Handycipher — Part 5 | 5 | 1090 | June 28, 2016 |
| Weakened Handycipher — Part 6 | 5 | 1090 | June 28, 2016 |
| The SIGABA Challenge — Part 4 | 5 | 13547 | March 17, 2020 |
| The Heavy T52 Sturgeon Challenge — Part 6 | 5 | 13561 | April 22, 2020 |
| The SZ42 Challenge — Part 10 | 5 | 1119 | Jan. 30, 2021 |
| Notes of an Italian Soldier | 4 | 0 | Oct. 14, 2010 |
| Handycipher — Part 4 | 4 | 13222 | June 28, 2016 |
| ElsieFour — Part 1 | 4 | 13305 | Oct. 3, 2017 |
| Weakened ElsieFour — Part 3 | 4 | 1095 | Oct. 3, 2017 |
| Christmas Challenge 2019: Differential Cryptanalysis — Part 1 | 4 | 1108 | Dec. 22, 2019 |
| Differential Cryptanalysis — Part 2 | 4 | 1109 | Jan. 28, 2020 |
| The SZ42 Challenge — Part 11 | 4 | 1119 | Jan. 30, 2021 |
| The Hutton Cipher – Part 3 | 4 | 1260 | July 21, 2023 |
| The Hutton Cipher – Part 4 | 4 | 1378 | Sept. 6, 2023 |
| Extended Handycipher — Part 1 | 3 | 1087 | March 27, 2015 |
| Extended Handycipher — Part 2 | 3 | 1087 | March 27, 2015 |
| Extended Handycipher — Part 3 | 3 | 1087 | March 27, 2015 |
| Extended Handycipher — Part 4 | 3 | 13222 | June 28, 2016 |
| Extended Handycipher — Part 5 | 3 | 13222 | June 28, 2016 |
| Handycipher — Part 8 | 3 | 13257 | Jan. 21, 2017 |
| Handycipher — Part 9 | 3 | 13257 | Jan. 21, 2017 |
| Holographic Encryption — Part 2 | 3 | 1093 | April 7, 2017 |
| The Vatican Challenge — Part 1 | 3 | 0 | Feb. 14, 2018 |
| The Vatican Challenge — Part 2 | 3 | 0 | Feb. 14, 2018 |
| The Heavy T52 Sturgeon Challenge — Part 9 | 3 | 13564 | April 30, 2020 |
| Double Column Transposition | 2 | 0 | Oct. 14, 2010 |
| Unknown Author | 2 | Variable | Oct. 14, 2010 |
| ORYX Stream Cipher — Part 4b | 2 | 13111 | April 14, 2014 |
| Extended Handycipher — Part 6 | 2 | 13222 | June 28, 2016 |
| Handycipher — Part 7 | 2 | 13257 | Jan. 21, 2017 |
| Catherine of Aragon's Letter to King Ferdinand, her Father (1509) | 2 | Variable | Nov. 28, 2018 |
| "The Road" — Part 2 | 2 | 1101 | Dec. 8, 2018 |
| The Heavy T52 Sturgeon Challenge — Part 1 | 2 | 13489 | Sept. 30, 2019 |
| The Heavy T52 Sturgeon Challenge — Part 2 | 2 | 13491 | Oct. 9, 2019 |
| The Heavy T52 Sturgeon Challenge — Part 3 | 2 | 13497 | Oct. 26, 2019 |
| The SIGABA Challenge — Part 5 | 2 | 13550 | March 26, 2020 |
| SIGABA CSP-889 — Part 1 | 2 | 1124 | June 1, 2021 |
| SIGABA CSP-889 — Part 2 | 2 | 1124 | June 1, 2021 |
| SIGABA CSP-889 — Part 3 | 2 | 13755 | June 1, 2021 |
| SIGABA CSP-2900 — Part 1 | 2 | 1126 | July 31, 2021 |
| SIGABA CSP-2900 — Part 2 | 2 | 1126 | July 31, 2021 |
| SIGABA CSP-2900 — Part 3 | 2 | 13794 | July 31, 2021 |
| Beale Ciphers | 1 | Variable | Oct. 14, 2010 |
| Substitution Cipher with Non-Prefix Codes | 1 | 13006 | June 15, 2011 |
| Monoalphabetic Substitution with Camouflage — Part 6 | 1 | 1080 | June 30, 2012 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 2 | 1 | 1090 | July 9, 2016 |
| Hilly — Part 2 | 1 | 1095 | Oct. 17, 2017 |
| Weakened ElsieFour — Part 2 | 1 | 1098 | April 28, 2018 |
| Handycipher — Part 10 | 1 | 1105 | June 25, 2019 |
| The Vatican Challenge — Part 4 | 1 | Variable | July 7, 2019 |
| The SIGABA Challenge — Part 6 | 1 | 13554 | April 5, 2020 |
| D'Agapeyeff | 0 | Variable | Oct. 14, 2010 |
| Dorabella | 0 | Variable | Oct. 14, 2010 |
| Kryptos | 0 | Variable | Oct. 14, 2010 |
| World Record Challenge: Break 65 Bits of AES | 0 | 12986 | Oct. 14, 2010 |
| Recovering the Private Key in the Fully Homomorphic Encryption Scheme | 0 | 12993 | Jan. 14, 2011 |
| Twelve-Year-Old Murder Case | 0 | Variable | April 7, 2011 |
| Kaskade-S/T — Part 4 | 0 | 1078 | May 5, 2011 |
| Digital Signatures: DSA with Medium Fields | 0 | 13013 | Sept. 2, 2011 |
| The third ENIGMA M4 message | 0 | Variable | Sept. 21, 2011 |
| RSA Factoring Challenge: RSA-260 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-270 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-896 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-280 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-290 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-300 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-309 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-1024 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-310 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-320 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-330 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-340 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-350 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-360 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-370 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-380 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-390 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-400 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-410 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-420 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-430 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-440 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-450 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-460 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-1536 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-470 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-480 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-490 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-500 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-617 | 0 | 13028 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-2048 | 0 | 13028 | Feb. 7, 2012 |
| ORYX Stream Cipher — Part 4d | 0 | 13078 | June 27, 2013 |
| Double Column Transposition Reloaded — Part 1 | 0 | 13097 | Dec. 11, 2013 |
| Double Column Transposition Reloaded — Part 2 | 0 | 13097 | Dec. 11, 2013 |
| Double Column Transposition Reloaded — Part 3 | 0 | 13097 | Dec. 11, 2013 |
| Spanish Strip Cipher — Part 3 | 0 | Variable | March 27, 2014 |
| ORYX Stream Cipher — Part 4c | 0 | 13111 | April 14, 2014 |
| Double-Column Transposition/Granit — Part 1 | 0 | 1087 | July 1, 2015 |
| Double-Column Transposition/Granit — Part 2 | 0 | 1087 | July 1, 2015 |
| Double-Column Transposition/Granit — Part 3 | 0 | 1087 | July 1, 2015 |
| Spirale — Part 4 | 0 | 13175 | Aug. 23, 2015 |
| Weakened Granit — Part 2 | 0 | 1088 | Sept. 24, 2015 |
| Weakened Granit — Part 3 | 0 | 1088 | Sept. 24, 2015 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 3 | 0 | 1090 | July 9, 2016 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 4 | 0 | 1090 | July 9, 2016 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 5 | 0 | 1090 | July 9, 2016 |
| "The Road" — Part 3 | 0 | 1101 | Dec. 8, 2018 |
| The Vatican Challenge — Part 3 | 0 | Variable | June 25, 2019 |
| The Vatican Challenge — Part 5 | 0 | Variable | July 7, 2019 |
| The Heavy T52 Sturgeon Challenge — Part 8 | 0 | 13562 | April 24, 2020 |
| A Heavy SZ42 Challenge – Part 14 | 0 | 14408 | Dec. 30, 2022 |