| The Syllabary Cipher – Part 1 | 103 | Dec. 1, 2022, 10:57 p.m. |
| Image Noise | 100 | Feb. 15, 2022, 3:07 a.m. |
| RSA Factoring Challenge: RSA-232 | 0 | Sept. 2, 2021, 8:01 p.m. |
| RSA Factoring Challenge: RSA-250 | 0 | Sept. 2, 2021, 7:57 p.m. |
| RSA Factoring Challenge: RSA-210 | 0 | Sept. 2, 2021, 7:53 p.m. |
| RSA Factoring Challenge: RSA-704 | 0 | Sept. 2, 2021, 7:50 p.m. |
| RSA Factoring Challenge: RSA-240 | 0 | Sept. 2, 2021, 7:48 p.m. |
| RSA Factoring Challenge: RSA-230 | 0 | Sept. 2, 2021, 7:45 p.m. |
| RSA Factoring Challenge: RSA-220 | 0 | Sept. 2, 2021, 7:42 p.m. |
| Wheatstone Cryptograph — Part 1 | 110 | April 30, 2021, 9:50 p.m. |
| M-138 — Part 4 | 1,094 | April 10, 2021, 9:42 p.m. |
| Homophonic Encryption — Part 4 | 1,131 | April 1, 2021, 9:35 p.m. |
| Homophonic Encryption — Part 3 | 1,131 | April 1, 2021, 8:55 p.m. |
| Homophonic Encryption — Part 2 | 1,131 | April 1, 2021, 4:42 p.m. |
| Homophonic Encryption — Part 1 | 1,140 | Nov. 3, 2020, 6:58 p.m. |
| Turing Bombe Enigma I | 100 | Nov. 3, 2020, 2:22 a.m. |
| Enigma Part 2 | 1,083 | Nov. 1, 2020, 7:19 p.m. |
| Polyhomophonic Substitution — Part 1 | 100 | Oct. 31, 2020, 10:57 p.m. |
| Find the right route — Part 1 | 125 | Oct. 30, 2020, 10:52 p.m. |
| Advent-Challenge — Part 2 | 1,120 | July 14, 2020, 6:41 p.m. |
| Weakened Granit — Part 1 | 100 | July 11, 2020, 5:40 p.m. |
| Hybrid Encryption I | 1,085 | Dec. 27, 2019, 5:57 p.m. |
| Summer Job | 1,139 | Dec. 25, 2019, 9:18 p.m. |
| Zodiac Cipher | 100 | Nov. 25, 2019, 10:25 p.m. |
| Advent Challenge — Part 3 | 1,144 | May 4, 2019, 3:53 a.m. |
| BCR code (Book-Caesar-RSA) | 1,093 | April 29, 2019, 1:53 p.m. |
| Number Sequence — Part 7 | 100 | April 26, 2019, 9:03 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,087 | April 16, 2019, 3:07 a.m. |
| Factorization Cipher — Part 2 | 1,090 | March 15, 2019, 9:40 p.m. |
| Broadcasting and low exponent — RSA Attack | 1,089 | March 10, 2019, 4:13 a.m. |
| Advent Challenge — Part 4 | 1,149 | March 8, 2019, 2:58 a.m. |
| Number Sequence — Part 9 | 100 | Feb. 28, 2019, 4:04 p.m. |
| Monoalphabetic Substitution with Nostradamus Flavor | 1,660 | Feb. 19, 2019, 4:02 p.m. |
| Cryptanalysis Hacking Puzzles — Part 2 | 105 | Jan. 31, 2019, 3:52 a.m. |
| Autokey Cipher | 113 | Oct. 2, 2018, 6:45 p.m. |
| RSA: Two different keys — same ciphertext | 1,091 | Sept. 8, 2018, 8 p.m. |
| Number Sequence — Part 10 | 101 | Aug. 9, 2018, 11:38 p.m. |
| Number Sequence — Part 5 | 100 | Aug. 9, 2018, 8:15 p.m. |
| Alice's Birthday Party (Part 2) | 1,089 | July 13, 2018, 10:32 p.m. |
| Alice's Birthday Party (Part 1) | 1,089 | July 13, 2018, 10:19 p.m. |
| Classical Ciphers^3 | 100 | June 14, 2018, 7:58 p.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | March 26, 2018, 5:57 p.m. |
| Enigma Combinatorics | 100 | March 21, 2018, 7:36 p.m. |
| The Einstein Enigma | 1,660 | Feb. 11, 2018, 4:56 a.m. |
| The Last Note | 100 | Feb. 6, 2018, 3:45 a.m. |
| ADFGVX — Part 1 | 100 | Feb. 4, 2018, 12:55 a.m. |
| Enigma Messages | 100 | Jan. 15, 2018, 4:24 a.m. |
| Enigma Messages with Repeated Letters — Part 4 | 100 | Jan. 15, 2018, 4:15 a.m. |
| Enigma Messages with Repeated Letters — Part 5 | 100 | Jan. 15, 2018, 4:06 a.m. |
| Enigma Messages with Repeated Letters — Part 3 | 100 | Jan. 15, 2018, 1:21 a.m. |
| Nils away on travel | 100 | Jan. 15, 2018, 12:47 a.m. |
| Molehunt (Part 2/3) | 100 | Jan. 12, 2018, 3:07 a.m. |
| Molehunt (Part 1/3) | 100 | Jan. 11, 2018, 8:31 p.m. |
| Cascading Encryption — Part 1/3 | 100 | Jan. 10, 2018, 11:01 p.m. |
| Recycled One-Time Pad | 100 | Jan. 9, 2018, 10:46 p.m. |
| M-138 — Part 3 | 1,115 | Jan. 8, 2018, 6:38 p.m. |
| M-138 — Part 2 | 1,115 | Jan. 7, 2018, 10:54 p.m. |
| Advent-Challenge — Part 1 | 110 | Dec. 17, 2017, 10:27 p.m. |
| Enigma Messages with Repeated Letters — Part 2 | 100 | June 21, 2017, 8:58 p.m. |
| Double Columnar Transposition | 100 | May 3, 2016, 5:53 p.m. |
| ECDH-Key Exchange for Beginners | 100 | Jan. 25, 2016, 9:28 p.m. |
| Hill Cipher with Sudoku Key | 100 | Jan. 25, 2016, 12:53 a.m. |
| ADFGVX — Part 2 | 100 | Jan. 5, 2016, 7:50 p.m. |
| Playfair Encryption | 100 | Dec. 28, 2015, 1:17 a.m. |
| One-Time Pad with Flaws | 100 | Dec. 27, 2015, 4:48 a.m. |
| Heartbleed — Part 2 | 100 | Dec. 25, 2015, 1:21 a.m. |
| Number Sequence — Part 6 | 100 | Dec. 11, 2015, 9:09 p.m. |
| Number Sequence — Part 8 | 101 | Dec. 11, 2015, 9:03 p.m. |
| Modified Caesar Cipher | 100 | April 26, 2015, 9:16 p.m. |
| M-138 — Part 1 | 101 | April 25, 2015, 1:56 p.m. |
| How do you become a big cryptographer? | 100 | April 24, 2015, 2:46 a.m. |
| Kaskade-S/T — Part 1 | 100 | April 23, 2015, 1:36 a.m. |
| Playfair with hints about the grid | 100 | Dec. 5, 2014, 2:23 p.m. |
| Trifid Cipher | 100 | Nov. 24, 2014, 8:40 p.m. |
| Letter to the Templars — Part 3 | 1,127 | Nov. 23, 2014, 2:40 p.m. |
| Letter to the Templars — Part 2 | 100 | Nov. 22, 2014, 2:07 p.m. |
| Letter to the Templars — Part 1 | 100 | Nov. 22, 2014, 4:12 a.m. |
| Reserve Hand Procedure — Part 1 | 100 | Nov. 11, 2014, 1:13 a.m. |
| Enigma Messages with Repeated Letters — Part 1 | 100 | Oct. 29, 2014, 1:34 a.m. |
| Multilingual Monoalphabetic Substitution | 100 | Oct. 26, 2014, 12:06 a.m. |
| Monoalphabetic Substitution | 100 | Oct. 18, 2014, 11:28 p.m. |
| The Book Code: A Challenge for Bookworms | 100 | Oct. 17, 2014, 9:27 p.m. |
| From Russia with Love | 100 | Sept. 29, 2014, 6:49 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | Sept. 27, 2014, 7:31 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | Sept. 25, 2014, 11:21 p.m. |
| Pigpen with a twist — Part 1 | 100 | Sept. 25, 2014, 6:10 p.m. |
| ¿No Hablas Español? No problemo! | 100 | Sept. 20, 2014, 10:03 p.m. |
| A hidden word | 100 | Sept. 10, 2014, 11:44 p.m. |
| Heartbleed — Part 1 | 108 | Sept. 8, 2014, 11:55 p.m. |
| Cracking SHA1-Hashed Passwords | 1,111 | Aug. 20, 2014, 3:06 a.m. |
| Grille Cipher | 100 | Aug. 20, 2014, 12:05 a.m. |
| Snow White and the seven dwarfs | 100 | Aug. 19, 2014, 6:36 p.m. |
| Factorization Cipher — Part 1 | 100 | Aug. 19, 2014, 4:18 a.m. |
| Number Sequence — Part 4 | 100 | Aug. 18, 2014, 10:31 p.m. |
| Number Sequence — Part 3 | 100 | Aug. 18, 2014, 10:16 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 100 | Aug. 18, 2014, 6:27 p.m. |
| Caesar Encryption | 100 | Aug. 13, 2014, 7:40 p.m. |
| Beaver Code | 100 | Aug. 13, 2014, 4:45 a.m. |
| Number Sequence — Part 2 | 100 | July 12, 2014, 1:09 a.m. |
| Original Caesar Cipher | 100 | July 11, 2014, 11:02 p.m. |
| Number Sequence | 100 | July 11, 2014, 5:21 p.m. |