| Number Sequence | 4389 | 100 | Oct. 14, 2010 |
| Original Caesar Cipher | 3095 | 100 | Dec. 15, 2010 |
| Number Sequence — Part 2 | 2164 | 100 | July 11, 2011 |
| Caesar Encryption | 1475 | 100 | Oct. 21, 2010 |
| Beaver Code | 1228 | 100 | Aug. 13, 2012 |
| Letter to the Templars — Part 1 | 1055 | 100 | July 16, 2012 |
| Number Sequence — Part 3 | 1048 | 100 | March 30, 2012 |
| A hidden word | 868 | 100 | Jan. 6, 2013 |
| Number Sequence — Part 4 | 864 | 100 | April 18, 2012 |
| Letter to the Templars — Part 2 | 845 | 100 | July 30, 2012 |
| Letter to the Templars — Part 3 | 721 | 1080 | Oct. 9, 2012 |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 610 | 100 | Sept. 9, 2011 |
| Cracking SHA1-Hashed Passwords | 583 | 1077 | April 4, 2011 |
| Monoalphabetic Substitution | 562 | 100 | Oct. 14, 2010 |
| Factorization Cipher — Part 1 | 519 | 100 | Oct. 17, 2011 |
| Advent-Challenge — Part 1 | 508 | 100 | Dec. 8, 2017 |
| Grille Cipher | 506 | 100 | Oct. 14, 2011 |
| Number Sequence — Part 8 | 415 | 100 | Sept. 14, 2015 |
| A modified homophonic cipher with reduced alphabets — Part 1 | 404 | 100 | Oct. 21, 2010 |
| A modified homophonic cipher with reduced alphabets — Part 2 | 349 | 100 | Oct. 21, 2010 |
| One-Time Pad with Flaws | 320 | 100 | Nov. 12, 2010 |
| Alice's Birthday Party (Part 1) | 312 | 1076 | Oct. 14, 2010 |
| Snow White and the seven dwarfs | 302 | 100 | April 20, 2013 |
| From Russia with Love | 299 | 100 | Sept. 4, 2013 |
| Alice's Birthday Party (Part 2) | 298 | 1076 | Oct. 14, 2010 |
| Broadcasting and low exponent — RSA Attack | 243 | 1078 | July 22, 2011 |
| Modified Caesar Cipher | 236 | 100 | Sept. 2, 2011 |
| How do you become a big cryptographer? | 234 | 100 | May 28, 2012 |
| M-138 — Part 1 | 230 | 100 | Dec. 24, 2014 |
| The Syllabary Cipher – Part 1 | 222 | 100 | Oct. 28, 2022 |
| Cryptanalysis Hacking Puzzles — Part 2 | 212 | 100 | Jan. 9, 2019 |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 208 | 1076 | Oct. 14, 2010 |
| Not-so-Secret Message from Malawi — Part I (RSA) | 207 | 1076 | Oct. 14, 2010 |
| Reserve Hand Procedure — Part 1 | 198 | 100 | March 6, 2013 |
| Autokey Cipher | 193 | 100 | Sept. 25, 2018 |
| Classical Ciphers^3 | 190 | 100 | Oct. 14, 2010 |
| Enigma Messages with Repeated Letters — Part 1 | 183 | 100 | Sept. 26, 2013 |
| Letter from the Alleged Countess Julie von Ortenburg | 181 | 100 | Oct. 14, 2010 |
| Nils away on travel | 181 | 100 | Aug. 8, 2013 |
| Hybrid Encryption I | 180 | 1077 | Nov. 2, 2010 |
| ¿No Hablas Español? No problemo! | 176 | 100 | April 18, 2012 |
| Image Noise | 169 | 100 | Nov. 20, 2015 |
| Number Sequence — Part 6 | 168 | 100 | March 23, 2015 |
| Molehunt (Part 1/3) | 161 | 100 | Oct. 23, 2010 |
| RSA: Two different keys — same ciphertext | 158 | 1078 | Aug. 15, 2011 |
| Pigpen with a twist — Part 1 | 158 | 100 | Sept. 5, 2011 |
| The Book Code: A Challenge for Bookworms | 156 | 100 | March 21, 2012 |
| Molehunt (Part 2/3) | 152 | 100 | Oct. 23, 2010 |
| Factorization Cipher — Part 2 | 150 | 1078 | Dec. 1, 2011 |
| M-138 — Part 2 | 140 | 1085 | Dec. 24, 2014 |
| Alberti Challenge — Part 1 | 137 | 100 | March 26, 2022 |
| A Secret Message from Castle Mansfeld | 132 | 100 | Oct. 14, 2010 |
| Enigma Part 1 | 132 | 1076 | Oct. 14, 2010 |
| Trifid Cipher | 131 | 100 | Oct. 28, 2013 |
| Playfair Encryption | 129 | 100 | Dec. 22, 2010 |
| ADFGVX — Part 2 | 127 | 100 | Aug. 15, 2011 |
| ADFGVX — Part 1 | 124 | 100 | Aug. 15, 2011 |
| Number Sequence — Part 9 | 124 | 100 | Nov. 16, 2017 |
| Number Sequence — Part 10 | 124 | 100 | April 18, 2018 |
| A really long number sequence | 123 | 1078 | Sept. 5, 2011 |
| Playfair with hints about the grid | 122 | 100 | Jan. 16, 2013 |
| Double Columnar Transposition | 119 | 100 | Oct. 12, 2011 |
| A hidden word — Part 2 | 117 | 100 | April 16, 2015 |
| Hill Cipher with Sudoku Key | 109 | 100 | Sept. 4, 2013 |
| Kaskade-S/T — Part 1 | 108 | 100 | March 4, 2011 |
| Number Sequence — Part 5 | 108 | 100 | April 18, 2012 |
| Enigma Combinatorics | 107 | 100 | Nov. 12, 2010 |
| Wheatstone Cryptograph — Part 1 | 105 | 100 | April 21, 2021 |
| The Last Note | 103 | 100 | Sept. 22, 2014 |
| ECDH-Key Exchange for Beginners | 102 | 100 | Feb. 24, 2012 |
| Zodiac Cipher | 101 | 100 | Oct. 14, 2010 |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 1 | 101 | 100 | April 7, 2011 |
| Number Sequence — Part 7 | 100 | 100 | March 23, 2015 |
| Factorization Cipher — Part 3 | 98 | 1078 | Jan. 6, 2012 |
| Find the right route — Part 1 | 94 | 100 | Oct. 27, 2020 |
| Enigma Part 2 | 92 | 1076 | Oct. 14, 2010 |
| Heartbleed — Part 1 | 90 | 0 | Aug. 28, 2014 |
| Partial Key Exposure with RSA — Part 1 | 89 | 1079 | Feb. 11, 2012 |
| Enigma Messages with Repeated Letters — Part 3 | 89 | 100 | March 5, 2014 |
| Enigma Messages with Repeated Letters — Part 2 | 88 | 100 | Oct. 28, 2013 |
| AES key — encoded in the machine readable zone of a European ePassport | 84 | 1079 | Jan. 16, 2012 |
| Molehunt (Part 3/3) | 83 | 1077 | Oct. 23, 2010 |
| Enigma Messages | 83 | 100 | Jan. 23, 2013 |
| Enigma Messages with Repeated Letters — Part 5 | 83 | 100 | March 5, 2014 |
| Modular Sequences | 83 | 100 | Sept. 25, 2018 |
| Multilingual Monoalphabetic Substitution | 82 | 100 | Jan. 30, 2013 |
| ORYX Stream Cipher Part I | 80 | 1076 | Oct. 14, 2010 |
| Enigma Messages with Repeated Letters — Part 4 | 80 | 100 | March 5, 2014 |
| Smartcard RSA | 77 | 1077 | Oct. 25, 2010 |
| Turing Bombe Enigma I | 75 | 100 | Oct. 17, 2011 |
| BCR code (Book-Caesar-RSA) | 75 | 1080 | Sept. 12, 2012 |
| Cascading Encryption — Part 1/3 | 75 | 100 | Jan. 25, 2013 |
| Recycled One-Time Pad | 71 | 100 | Nov. 20, 2012 |
| Unusual encryption using a diophantine equation | 69 | 1078 | Sept. 2, 2011 |
| RSA Factoring Challenge: RSA-704 | 69 | 0 | July 31, 2013 |
| Merkle-Hellman Knapsack Challenge - Part 1 | 68 | 100 | Oct. 14, 2022 |
| Monoalphabetic substitution with camouflage — Part 1 | 66 | 100 | Oct. 27, 2011 |
| M-138 — Part 3 | 65 | 1085 | Dec. 24, 2014 |
| RSA Factoring Challenge: RSA-210 | 64 | 0 | Feb. 7, 2012 |
| An Invisible Message | 63 | 100 | Oct. 17, 2011 |
| The Einstein Enigma | 62 | 1095 | Feb. 7, 2018 |
| Lightweight Introduction to Lattices — Part 1 | 61 | 100 | May 16, 2020 |
| Heartbleed — Part 2 | 60 | 0 | Aug. 28, 2014 |
| News from Castle Mansfeld | 60 | 100 | Nov. 13, 2015 |
| Summer Job | 59 | 1096 | June 12, 2018 |
| Advent-Challenge — Part 2 | 57 | 1094 | Dec. 16, 2017 |
| Polyhomophonic Substitution — Part 1 | 56 | 100 | March 22, 2020 |
| Monoalphabetic substitution with camouflage — Part 2 | 54 | 1078 | Dec. 7, 2011 |
| New Year's Greetings — Part 1 | 54 | 100 | March 21, 2016 |
| Kaskade-S/T — Part 2 | 53 | 1077 | March 4, 2011 |
| Unconcealed RSA messages | 52 | 1078 | Nov. 2, 2011 |
| Double Column Transposition — Part 4 | 52 | 1083 | May 19, 2014 |
| Weakened Granit — Part 1 | 52 | 100 | Sept. 24, 2015 |
| Monoalphabetic substitution with camouflage — Part 4 | 51 | 100 | Dec. 21, 2011 |
| Strange Message from Thessaloniki | 51 | 100 | Dec. 10, 2012 |
| Monoalphabetic substitution with camouflage — Part 3 | 50 | 1078 | Dec. 7, 2011 |
| Keyshanc — Part 1 | 50 | 1079 | May 21, 2012 |
| Lunchtime Attack on the Fully Homomorphic Encryption Scheme | 49 | 1077 | Jan. 14, 2011 |
| New Year's Greetings — Part 2 | 49 | 100 | March 21, 2016 |
| ORYX Stream Cipher Part II | 48 | 1076 | Oct. 14, 2010 |
| Advent Challenge — Part 3 | 48 | 1094 | Dec. 22, 2017 |
| RSA Factoring Challenge: RSA-220 | 47 | 0 | Feb. 7, 2012 |
| Double Column Transposition — Part 2 | 47 | 1083 | May 2, 2014 |
| New Year's Greetings — Part 3 | 47 | 100 | March 21, 2016 |
| CMEA 1 | 45 | 1077 | Dec. 6, 2010 |
| Advent Challenge — Part 4 | 45 | 1094 | Dec. 21, 2017 |
| Not-so-Secret Message from Malawi — Part II (ECC) | 44 | 1076 | Oct. 14, 2010 |
| An 'unhearable' message | 44 | 100 | June 5, 2012 |
| New Year's Greetings — Part 4 | 44 | 100 | March 21, 2016 |
| Homophonic Encryption — Part 1 | 44 | 1101 | May 4, 2019 |
| Lightweight Introduction to Lattices — Part 2 | 44 | 100 | June 23, 2020 |
| Music Code — Part 1 | 43 | 100 | May 17, 2011 |
| Pigpen with a twist — Part 2 | 43 | 1078 | Sept. 2, 2011 |
| Ku Klux Klan | 42 | Variable | Oct. 14, 2010 |
| Music Code — Part 2 | 42 | 1077 | May 17, 2011 |
| Pigpen with a twist — Part 3 | 41 | 1078 | Sept. 2, 2011 |
| Keyshanc — Part 2 | 41 | 1079 | May 21, 2012 |
| Double Column Transposition — Part 3 | 41 | 1083 | May 2, 2014 |
| RSA Factoring Challenge: RSA-230 | 40 | 0 | Feb. 7, 2012 |
| Fastest in the West | 40 | 1096 | June 12, 2018 |
| Homophonic Encryption — Part 2 | 39 | 1101 | May 8, 2019 |
| Monoalphabetic Substitution with Nostradamus Flavor | 38 | 1100 | Feb. 16, 2019 |
| Trendy Messenger | 37 | 1096 | June 12, 2018 |
| Homophonic Encryption — Part 3 | 37 | 1101 | May 8, 2019 |
| Homophonic Encryption — Part 4 | 37 | 1101 | May 8, 2019 |
| Lightweight Introduction to Lattices — Part 3 | 37 | 1109 | July 16, 2020 |
| Kaskade-S/T — Part 3 | 36 | 1077 | March 4, 2011 |
| Find the right route — Part 2 | 35 | 100 | Dec. 19, 2020 |
| Lattice Part 1 | 34 | 1077 | March 11, 2011 |
| Monoalphabetic Substitution with Camouflage — Part 5 | 34 | 1079 | March 9, 2012 |
| Spanish Strip Cipher — Part 1 | 34 | 1083 | March 27, 2014 |
| Double Column Transposition — Part 1 | 34 | 1083 | April 4, 2014 |
| Spanish Strip Cipher — Part 2 | 33 | 1083 | 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 3 | 33 | 100 | Dec. 26, 2020 |
| Typex — Part 1 | 31 | 1081 | Feb. 28, 2013 |
| ORYX Stream Cipher — Part 3 (revised) | 31 | 1081 | June 6, 2013 |
| M-138 — Part 4 | 31 | 1085 | Dec. 24, 2014 |
| CMEA 2 | 29 | 12976 | Dec. 6, 2010 |
| AES ECB Wrong Encoding | 29 | 1094 | Dec. 16, 2017 |
| Polyhomophonic Substitution — Part 2 | 29 | 1107 | March 28, 2020 |
| RSA Factoring Challenge: RSA-232 | 28 | 0 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-240 | 28 | 0 | Feb. 7, 2012 |
| Handycipher made in love — Part 1 | 28 | 1100 | Feb. 16, 2019 |
| The LoRa Cipher: Logic Randomness — Part 1 | 28 | 1106 | Feb. 19, 2020 |
| RSA Factoring Challenge: RSA-250 | 27 | 0 | Feb. 7, 2012 |
| Typex — Part 2 | 25 | 1081 | April 3, 2013 |
| Polyphonic Substitution Cipher — Part 1 | 25 | 1104 | Nov. 21, 2019 |
| The Syllabary Cipher – Part 2 | 25 | 1143 | Oct. 28, 2022 |
| RSA with Special d | 24 | 12972 | Oct. 14, 2010 |
| Polyphonic Substitution Cipher — Part 2 | 23 | 1105 | Jan. 14, 2020 |
| Handycipher made in love — Part 2 | 22 | 1101 | May 21, 2019 |
| A Cloaked Substitution Cipher — Part 1 | 22 | 1103 | Aug. 21, 2019 |
| Purple 1 | 21 | 1077 | Oct. 27, 2010 |
| Cascading Encryption — Part 2/3 | 21 | 1081 | March 25, 2013 |
| A Cloaked Substitution Cipher — Part 2 | 21 | 1103 | Aug. 25, 2019 |
| Flawed Usage of a OTP Cipher by the BND | 20 | 1086 | Aug. 23, 2015 |
| Breaking a Filter Generator | 20 | 1098 | Sept. 25, 2018 |
| The T52 Sturgeon Challenge — Part 1 | 20 | 1102 | July 13, 2019 |
| A disguised code | 20 | 101 | Oct. 31, 2023 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 1 | 19 | 1089 | July 9, 2016 |
| The T52 Sturgeon Challenge — Part 2 | 19 | 1102 | July 22, 2019 |
| The SZ42 Challenge — Part 1 | 19 | 1109 | July 22, 2020 |
| The Syllabary Cipher – Part 3 | 19 | 1143 | Oct. 28, 2022 |
| The Hutton Cipher – Part 1 | 19 | 1163 | May 2, 2023 |
| The Hutton Cipher – Part 2 | 19 | 1169 | June 5, 2023 |
| Sigaba Part 1 | 18 | 1076 | Oct. 14, 2010 |
| Cipher ID — Part 1 | 18 | 1104 | Nov. 19, 2019 |
| Polyhomophonic Substitution — Part 3 | 18 | 1107 | April 6, 2020 |
| The SZ42 Challenge — Part 2 | 18 | 1109 | Aug. 5, 2020 |
| Weakened Handycipher — Part 1 | 17 | 1086 | May 13, 2015 |
| Concealed Messages — Vigenère's Night Sky | 16 | 0 | May 1, 2012 |
| New Year's Greetings — Part 5 | 16 | 1088 | March 21, 2016 |
| The SZ42 Challenge — Part 3 | 16 | 1110 | Aug. 15, 2020 |
| The SZ42 Challenge — Part 4 | 16 | 1110 | Aug. 29, 2020 |
| The SZ42 Challenge — Part 5 | 16 | 1110 | Sept. 3, 2020 |
| Merkle-Hellman Knapsack Challenge — Part 2 | 16 | 1142 | Oct. 14, 2022 |
| Weakened Handycipher — Part 2 | 15 | 1086 | May 13, 2015 |
| Weakened Handycipher — Part 3 | 15 | 1086 | May 13, 2015 |
| The T52 Sturgeon Challenge — Part 3 | 15 | 1102 | July 22, 2019 |
| Wheatstone Cryptograph — Part 2 | 15 | 1117 | May 21, 2021 |
| The Josse Challenge – Part 1 | 15 | 1153 | Feb. 10, 2023 |
| The Josse Challenge – Part 2 | 15 | 1154 | Feb. 25, 2023 |
| Cascading Encryption — Part 3/3 | 14 | 1081 | March 29, 2013 |
| The SZ42 Challenge — Part 6 | 14 | 1111 | Oct. 2, 2020 |
| The SZ42 Challenge — Part 8 | 14 | 1111 | Oct. 31, 2020 |
| The T52 Sturgeon Challenge — Part 4 | 13 | 1102 | July 22, 2019 |
| The SZ42 Challenge — Part 7 | 13 | 1111 | Oct. 27, 2020 |
| The SZ42 Challenge — Part 9 | 13 | 1113 | Dec. 19, 2020 |
| The Syllabary Cipher – Part 4 | 13 | 1143 | Oct. 28, 2022 |
| The Syllabary Cipher – Part 5 | 13 | 1143 | Oct. 28, 2022 |
| The Josse Challenge – Part 3 | 13 | 1158 | March 27, 2023 |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 2 | 12 | 1077 | April 13, 2011 |
| ORYX Stream Cipher — Part 4a | 12 | 1083 | April 14, 2014 |
| Hill Cipher | 12 | 1139 | Sept. 4, 2022 |
| Modified Vigenère Cipher | 11 | 1127 | Jan. 24, 2022 |
| Akelarre Part 1 | 10 | 1077 | Nov. 24, 2010 |
| Kaskade-S/T — Part 5 | 10 | 1077 | May 5, 2011 |
| The T52 Sturgeon Challenge — Part 8 | 10 | 1102 | Aug. 10, 2019 |
| The SIGABA Challenge — Part 1 | 10 | 1106 | Feb. 29, 2020 |
| Alberti Challenge — Part 2 | 10 | 1132 | May 14, 2022 |
| Double Column Transposition — Part 5 | 9 | 1083 | June 23, 2014 |
| Hilly — Part 1 | 9 | 1091 | Jan. 25, 2017 |
| "The Road" — Part 1 | 9 | 1099 | Dec. 8, 2018 |
| The T52 Sturgeon Challenge — Part 11 | 9 | 1102 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 12 | 9 | 1102 | Aug. 10, 2019 |
| The SIGABA Challenge — Part 2 | 9 | 1106 | March 5, 2020 |
| The SZ42 Challenge — Part 12 | 9 | 1122 | Oct. 6, 2021 |
| Handycipher — Part 2 | 8 | 1085 | March 3, 2015 |
| Spirale — Part 1 | 8 | 1086 | Aug. 23, 2015 |
| Spirale — Part 2 | 8 | 1086 | Aug. 23, 2015 |
| The T52 Sturgeon Challenge — Part 9 | 8 | 1102 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 10 | 8 | 1102 | Aug. 10, 2019 |
| The SZ42 Challenge — Part 13 | 8 | 1122 | Oct. 6, 2021 |
| Handycipher — Part 3 | 7 | 13129 | March 3, 2015 |
| Holographic Encryption — Part 1 | 7 | 1091 | April 7, 2017 |
| The T52 Sturgeon Challenge — Part 5 | 7 | 1102 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 6 | 7 | 1102 | Aug. 10, 2019 |
| The T52 Sturgeon Challenge — Part 7 | 7 | 1102 | Aug. 10, 2019 |
| The Heavy T52 Sturgeon Challenge — Part 7 | 7 | 13499 | April 23, 2020 |
| Handycipher — Part 1 | 6 | 1085 | March 3, 2015 |
| Spirale — Part 3 | 6 | 1086 | Aug. 23, 2015 |
| Weakened Handycipher — Part 4 | 6 | 1089 | June 28, 2016 |
| Weakened Handycipher — Part 5 | 6 | 1089 | June 28, 2016 |
| Weakened Handycipher — Part 6 | 6 | 1089 | June 28, 2016 |
| Kaskade-S/T — Part 6 (RansomKaskade Part 1) | 6 | 1092 | July 2, 2017 |
| Weakened ElsieFour — Part 1 | 6 | 1096 | April 28, 2018 |
| The SIGABA Challenge — Part 3 | 6 | 13485 | March 11, 2020 |
| The Heavy T52 Sturgeon Challenge — Part 4 | 6 | 13496 | April 15, 2020 |
| The Heavy T52 Sturgeon Challenge — Part 5 | 6 | 13498 | April 21, 2020 |
| Sigaba Part 2 | 5 | 12972 | Oct. 14, 2010 |
| Handycipher — Part 5 | 5 | 13195 | June 28, 2016 |
| Handycipher — Part 6 | 5 | 13195 | June 28, 2016 |
| Christmas Challenge 2019: Differential Cryptanalysis — Part 1 | 5 | 1105 | Dec. 22, 2019 |
| Differential Cryptanalysis — Part 2 | 5 | 1105 | Jan. 28, 2020 |
| The SIGABA Challenge — Part 4 | 5 | 13487 | March 17, 2020 |
| The Heavy T52 Sturgeon Challenge — Part 6 | 5 | 13499 | April 22, 2020 |
| The SZ42 Challenge — Part 10 | 5 | 1114 | Jan. 30, 2021 |
| Notes of an Italian Soldier | 4 | 0 | Oct. 14, 2010 |
| Handycipher — Part 4 | 4 | 13195 | June 28, 2016 |
| ElsieFour — Part 1 | 4 | 13271 | Oct. 3, 2017 |
| Weakened ElsieFour — Part 3 | 4 | 1093 | Oct. 3, 2017 |
| The SZ42 Challenge — Part 11 | 4 | 1114 | Jan. 30, 2021 |
| The Hutton Cipher – Part 3 | 4 | 1177 | July 21, 2023 |
| The Hutton Cipher – Part 4 | 4 | 1189 | Sept. 6, 2023 |
| Extended Handycipher — Part 1 | 3 | 1085 | March 27, 2015 |
| Extended Handycipher — Part 2 | 3 | 1085 | March 27, 2015 |
| Extended Handycipher — Part 3 | 3 | 1085 | March 27, 2015 |
| Extended Handycipher — Part 4 | 3 | 13195 | June 28, 2016 |
| Extended Handycipher — Part 5 | 3 | 13195 | June 28, 2016 |
| Handycipher — Part 8 | 3 | 13227 | Jan. 21, 2017 |
| Handycipher — Part 9 | 3 | 13227 | Jan. 21, 2017 |
| Holographic Encryption — Part 2 | 3 | 1091 | 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 2 | 3 | 13438 | Oct. 9, 2019 |
| The Heavy T52 Sturgeon Challenge — Part 3 | 3 | 13443 | Oct. 26, 2019 |
| The Heavy T52 Sturgeon Challenge — Part 9 | 3 | 13501 | April 30, 2020 |
| Double Column Transposition | 2 | 0 | Oct. 14, 2010 |
| Unknown Author | 2 | Variable | Oct. 14, 2010 |
| Monoalphabetic Substitution with Camouflage — Part 6 | 2 | 1079 | June 30, 2012 |
| ORYX Stream Cipher — Part 4b | 2 | 13091 | April 14, 2014 |
| Extended Handycipher — Part 6 | 2 | 13195 | June 28, 2016 |
| Handycipher — Part 7 | 2 | 13227 | Jan. 21, 2017 |
| Catherine of Aragon's Letter to King Ferdinand, her Father (1509) | 2 | Variable | Nov. 28, 2018 |
| "The Road" — Part 2 | 2 | 1099 | Dec. 8, 2018 |
| The Heavy T52 Sturgeon Challenge — Part 1 | 2 | 13436 | Sept. 30, 2019 |
| The SIGABA Challenge — Part 5 | 2 | 13490 | March 26, 2020 |
| SIGABA CSP-889 — Part 1 | 2 | 1117 | June 1, 2021 |
| SIGABA CSP-889 — Part 2 | 2 | 1117 | June 1, 2021 |
| SIGABA CSP-889 — Part 3 | 2 | 13661 | June 1, 2021 |
| SIGABA CSP-2900 — Part 1 | 2 | 1119 | July 31, 2021 |
| SIGABA CSP-2900 — Part 2 | 2 | 1119 | July 31, 2021 |
| SIGABA CSP-2900 — Part 3 | 2 | 13691 | July 31, 2021 |
| Elliptic Boogaloo – Part 1 | 2 | 1222 | Nov. 27, 2023 |
| Elliptic Boogaloo – Part 2 | 2 | 15456 | Jan. 15, 2024 |
| Elliptic Boogaloo – Part 3 | 2 | 17290 | March 9, 2024 |
| Beale Ciphers | 1 | Variable | Oct. 14, 2010 |
| Substitution Cipher with Non-Prefix Codes | 1 | 12991 | June 15, 2011 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 2 | 1 | 1089 | July 9, 2016 |
| Hilly — Part 2 | 1 | 1093 | Oct. 17, 2017 |
| Weakened ElsieFour — Part 2 | 1 | 1096 | April 28, 2018 |
| Handycipher — Part 10 | 1 | 1102 | June 25, 2019 |
| The Vatican Challenge — Part 4 | 1 | Variable | July 7, 2019 |
| The SIGABA Challenge — Part 6 | 1 | 13493 | 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 | 12972 | Oct. 14, 2010 |
| Recovering the Private Key in the Fully Homomorphic Encryption Scheme | 0 | 12979 | Jan. 14, 2011 |
| Twelve-Year-Old Murder Case | 0 | Variable | April 7, 2011 |
| Kaskade-S/T — Part 4 | 0 | 1077 | May 5, 2011 |
| Digital Signatures: DSA with Medium Fields | 0 | 12998 | Sept. 2, 2011 |
| The third ENIGMA M4 message | 0 | Variable | Sept. 21, 2011 |
| RSA Factoring Challenge: RSA-260 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-270 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-896 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-280 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-290 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-300 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-309 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-1024 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-310 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-320 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-330 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-340 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-350 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-360 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-370 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-380 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-390 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-400 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-410 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-420 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-430 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-440 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-450 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-460 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-1536 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-470 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-480 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-490 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-500 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-617 | 0 | 13012 | Feb. 7, 2012 |
| RSA Factoring Challenge: RSA-2048 | 0 | 13012 | Feb. 7, 2012 |
| ORYX Stream Cipher — Part 4d | 0 | 13060 | June 27, 2013 |
| Double Column Transposition Reloaded — Part 1 | 0 | 13077 | Dec. 11, 2013 |
| Double Column Transposition Reloaded — Part 2 | 0 | 13077 | Dec. 11, 2013 |
| Double Column Transposition Reloaded — Part 3 | 0 | 13077 | Dec. 11, 2013 |
| Spanish Strip Cipher — Part 3 | 0 | Variable | March 27, 2014 |
| ORYX Stream Cipher — Part 4c | 0 | 13091 | April 14, 2014 |
| Double-Column Transposition/Granit — Part 1 | 0 | 1086 | July 1, 2015 |
| Double-Column Transposition/Granit — Part 2 | 0 | 1086 | July 1, 2015 |
| Double-Column Transposition/Granit — Part 3 | 0 | 1086 | July 1, 2015 |
| Spirale — Part 4 | 0 | 13151 | Aug. 23, 2015 |
| Weakened Granit — Part 2 | 0 | 1087 | Sept. 24, 2015 |
| Weakened Granit — Part 3 | 0 | 1087 | Sept. 24, 2015 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 3 | 0 | 1089 | July 9, 2016 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 4 | 0 | 1089 | July 9, 2016 |
| ASAC — A Strong(er) ADFGVX Cipher — Part 5 | 0 | 1089 | July 9, 2016 |
| "The Road" — Part 3 | 0 | 1099 | 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 | 13499 | April 24, 2020 |
| A Heavy SZ42 Challenge – Part 14 | 0 | 14108 | Dec. 30, 2022 |
| The Hutton Cipher – Part 5 | 0 | 1202 | Oct. 16, 2023 |