| The Einstein Enigma | 1,106 | March 21, 2022, 8:34 p.m. |
| RSA Factoring Challenge: RSA-232 | 0 | March 19, 2022, 9:43 p.m. |
| RSA Factoring Challenge: RSA-240 | 0 | March 19, 2022, 9:42 p.m. |
| RSA Factoring Challenge: RSA-250 | 0 | March 19, 2022, 9:41 p.m. |
| Fastest in the West | 1,108 | March 12, 2022, 11:40 p.m. |
| Not-so-Secret Message from Malawi — Part II (ECC) | 1,080 | March 12, 2022, 5:58 a.m. |
| Trendy Messenger | 1,108 | March 7, 2022, 1:28 a.m. |
| Double Column Transposition — Part 4 | 1,089 | March 2, 2022, 11:21 p.m. |
| Double Column Transposition — Part 3 | 1,088 | March 2, 2022, 8:42 p.m. |
| Double Column Transposition — Part 1 | 1,088 | March 2, 2022, 7:33 p.m. |
| Double Column Transposition — Part 2 | 1,088 | March 2, 2022, 7:04 a.m. |
| Typex — Part 1 | 1,085 | March 2, 2022, 5:48 a.m. |
| RSA Factoring Challenge: RSA-230 | 0 | March 2, 2022, 3:18 a.m. |
| RSA Factoring Challenge: RSA-220 | 0 | March 2, 2022, 3:17 a.m. |
| RSA Factoring Challenge: RSA-210 | 0 | March 2, 2022, 3:17 a.m. |
| Summer Job | 1,109 | March 2, 2022, 1:19 a.m. |
| The T52 Sturgeon Challenge — Part 2 | 1,120 | March 1, 2022, 5:38 a.m. |
| The T52 Sturgeon Challenge — Part 4 | 1,121 | Feb. 7, 2022, 5:11 p.m. |
| The T52 Sturgeon Challenge — Part 1 | 1,121 | Jan. 25, 2022, 9:50 p.m. |
| From Russia with Love | 102 | Nov. 4, 2013, 5:29 a.m. |
| Enigma Messages with Repeated Letters — Part 2 | 120 | Nov. 2, 2013, 4:20 a.m. |
| Enigma Messages with Repeated Letters — Part 1 | 103 | Nov. 2, 2013, 3:50 a.m. |
| RSA Factoring Challenge: RSA-704 | 0 | Oct. 10, 2013, 5:47 a.m. |
| Typex — Part 2 | 2,000 | April 4, 2013, 3:51 a.m. |
| Cascading Encryption — Part 1/3 | 102 | March 29, 2013, 2:24 a.m. |
| Multilingual Monoalphabetic Substitution | 102 | March 19, 2013, 3:27 a.m. |
| Reserve Hand Procedure — Part 1 | 108 | March 19, 2013, 2:53 a.m. |
| Playfair with hints about the grid | 150 | Jan. 17, 2013, 7:26 p.m. |
| A hidden word | 200 | Jan. 6, 2013, 10:33 p.m. |
| Recycled One-Time Pad | 108 | Dec. 2, 2012, 6:14 a.m. |
| Letter to the Templars — Part 3 | 2,000 | Oct. 10, 2012, 6:24 a.m. |
| BCR code (Book-Caesar-RSA) | 2,000 | Sept. 12, 2012, 10:05 p.m. |
| Beaver Code | 200 | Aug. 14, 2012, 4:25 a.m. |
| Letter to the Templars — Part 2 | 200 | July 30, 2012, 11:55 p.m. |
| Letter to the Templars — Part 1 | 200 | July 16, 2012, 10:40 p.m. |
| An 'unhearable' message | 104 | July 3, 2012, 2:28 a.m. |
| Number Sequence — Part 5 | 101 | July 3, 2012, 12:22 a.m. |
| How do you become a big cryptographer? | 104 | June 20, 2012, 6:28 a.m. |
| Keyshanc — Part 2 | 2,000 | May 22, 2012, 12:25 a.m. |
| Keyshanc — Part 1 | 2,000 | May 22, 2012, 12:08 a.m. |
| Number Sequence — Part 4 | 114 | April 25, 2012, 5:35 a.m. |
| ¿No Hablas Español? No problemo! | 200 | April 18, 2012, 8:36 p.m. |
| CMEA 2 | 14,050 | April 11, 2012, 12:54 a.m. |
| Number Sequence — Part 3 | 200 | March 31, 2012, 7:13 a.m. |
| The Book Code: A Challenge for Bookworms | 200 | March 21, 2012, 7:27 p.m. |
| CMEA 1 | 1,147 | March 16, 2012, 1:39 a.m. |
| Monoalphabetic Substitution with Camouflage — Part 5 | 1,824 | March 11, 2012, 12:47 a.m. |
| Purple 1 | 1,144 | March 10, 2012, 1:24 a.m. |
| Monoalphabetic substitution with camouflage — Part 3 | 1,242 | March 1, 2012, 9:43 p.m. |
| Monoalphabetic substitution with camouflage — Part 2 | 1,242 | March 1, 2012, 7:26 p.m. |
| Monoalphabetic substitution with camouflage — Part 4 | 101 | Feb. 28, 2012, 8:32 p.m. |
| ECDH-Key Exchange for Beginners | 200 | Feb. 24, 2012, 5:50 a.m. |
| Unconcealed RSA messages | 1,222 | Feb. 23, 2012, 2:45 a.m. |
| Partial Key Exposure with RSA — Part 1 | 2,000 | Feb. 11, 2012, 8:11 p.m. |
| AES key — encoded in the machine readable zone of a European ePassport | 2,000 | Jan. 16, 2012, 10:06 p.m. |
| Factorization Cipher — Part 3 | 1,824 | Jan. 8, 2012, 4:54 a.m. |
| Factorization Cipher — Part 2 | 2,000 | Dec. 2, 2011, 6:35 a.m. |
| Monoalphabetic substitution with camouflage — Part 1 | 117 | Nov. 1, 2011, 5:02 p.m. |
| Pigpen with a twist — Part 3 | 1,288 | Oct. 20, 2011, 9:40 p.m. |
| Lattice Part 1 | 1,181 | Oct. 20, 2011, 5:13 p.m. |
| An Invisible Message | 200 | Oct. 17, 2011, 10:25 p.m. |
| Factorization Cipher — Part 1 | 200 | Oct. 17, 2011, 8:42 p.m. |
| Turing Bombe Enigma I | 200 | Oct. 17, 2011, 8:20 p.m. |
| Grille Cipher | 200 | Oct. 14, 2011, 8:55 p.m. |
| Double Columnar Transposition | 200 | Oct. 13, 2011, 5:35 a.m. |
| A really long number sequence | 1,485 | Sept. 15, 2011, 7:44 p.m. |
| Affine Codes / Modulo Arithmetic with N / Extended Euclid | 200 | Sept. 9, 2011, 4:07 p.m. |
| Pigpen with a twist — Part 2 | 1,576 | Sept. 7, 2011, 5:13 p.m. |
| Pigpen with a twist — Part 1 | 200 | Sept. 5, 2011, 10:17 p.m. |
| ORYX Stream Cipher Part II | 1,163 | Sept. 4, 2011, 8:05 a.m. |
| ORYX Stream Cipher Part I | 1,163 | Sept. 4, 2011, 7:18 a.m. |
| Modified Caesar Cipher | 200 | Sept. 3, 2011, 2:04 a.m. |
| Unusual encryption using a diophantine equation | 2,000 | Sept. 3, 2011, 1:48 a.m. |
| Smartcard RSA | 1,166 | Aug. 24, 2011, 7:39 p.m. |
| ADFGVX — Part 1 | 200 | Aug. 16, 2011, 1:43 a.m. |
| ADFGVX — Part 2 | 200 | Aug. 15, 2011, 10:52 p.m. |
| RSA: Two different keys — same ciphertext | 2,000 | Aug. 15, 2011, 8:37 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,166 | Aug. 14, 2011, 6:56 a.m. |
| Kaskade-S/T — Part 3 | 1,200 | Aug. 12, 2011, 5:07 a.m. |
| Molehunt (Part 3/3) | 1,170 | July 31, 2011, 9:33 p.m. |
| Enigma Part 1 | 1,168 | July 31, 2011, 4:44 a.m. |
| Hybrid Encryption I | 1,172 | July 30, 2011, 6:27 p.m. |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 1,169 | July 28, 2011, 6:26 a.m. |
| Enigma Part 2 | 1,169 | July 26, 2011, 6:22 p.m. |
| Kaskade-S/T — Part 2 | 1,207 | July 24, 2011, 9:27 a.m. |
| Broadcasting and low exponent — RSA Attack | 2,000 | July 22, 2011, 10:39 p.m. |
| Alice's Birthday Party (Part 2) | 1,170 | July 21, 2011, 7:27 a.m. |
| Kaskade-S/T — Part 1 | 101 | July 20, 2011, 9:40 p.m. |
| Alice's Birthday Party (Part 1) | 1,170 | July 19, 2011, 6:11 a.m. |
| A Secret Message from Castle Mansfeld | 100 | July 18, 2011, 6:29 a.m. |
| Letter from the Alleged Countess Julie von Ortenburg | 100 | July 18, 2011, 3:08 a.m. |
| Music Code — Part 2 | 1,268 | July 18, 2011, 12:28 a.m. |
| Music Code — Part 1 | 102 | July 18, 2011, 12:10 a.m. |
| One-Time Pad with Flaws | 100 | July 16, 2011, 8:40 a.m. |
| Classical Ciphers^3 | 100 | July 15, 2011, 5:47 p.m. |
| Post-Quantum Cryptography: Unbalanced Oil and Vinegar System — Part 1 | 101 | July 14, 2011, 11:57 p.m. |
| Lunchtime Attack on the Fully Homomorphic Encryption Scheme | 1,193 | July 12, 2011, 11:50 p.m. |
| Playfair Encryption | 100 | July 12, 2011, 5:10 a.m. |
| Number Sequence — Part 2 | 200 | July 11, 2011, 7:36 p.m. |
| Molehunt (Part 2/3) | 100 | June 30, 2011, 11:56 p.m. |
| Molehunt (Part 1/3) | 100 | June 30, 2011, 11:38 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 100 | June 30, 2011, 8:53 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | June 30, 2011, 6:08 p.m. |
| Enigma Combinatorics | 100 | June 30, 2011, 1:15 a.m. |
| Cracking SHA1-Hashed Passwords | 1,241 | June 29, 2011, 11:32 p.m. |
| Ku Klux Klan | 2,000 | June 14, 2011, 8:39 a.m. |
| Beale Ciphers | 150 | June 14, 2011, 4:10 a.m. |
| Monoalphabetic Substitution | 100 | June 14, 2011, 2:31 a.m. |
| Number Sequence | 100 | June 14, 2011, 1:46 a.m. |
| Zodiac Cipher | 100 | June 14, 2011, 1:38 a.m. |
| Caesar Encryption | 100 | June 14, 2011, 12:59 a.m. |
| Original Caesar Cipher | 101 | June 14, 2011, 12:27 a.m. |
Gold9
Silver5
Bronze5
