| Jellybean | ZzCrook ◪ | 2004-02-14 |
| 95 |
| Journey to Mars | ZzCrook ◪ | |
| 108 |
| Jet Pack Man 2 Demo | T-Bone ◪ | | No reviews. | 93 |
| Jet Pack Man | T-Bone ◪ | 2004-05-17 | No reviews. | 116 |
| Jump n Bump | Slinky Games | | No reviews. | 93 |
| Jimmy Demo | Slinky Games | |
| 91 |
| Johnny Pest | Robert Bloom | |
| 98 |
| Joe Shmoe: Savior of Shoes (Demo) | Nahah ◪ | 2006-01-14 |
| 79 |
| Jay & Andrew vs. the Nazi Teacher Party (unfinished) (ver. 0.0) | misterhaan ◪ | 1997-09-05 |
| 94 |
| Jewel of Arc Teaser | LostOne ◪ | 2004-02-17 |
| 81 |
| Jail Brake | Koji ◪ | |
| 99 |
| Jiffy 1-4 | Joel Smith | |
| 99 |
| Jack: Time to Save the World | Jason Weaver | |
| 96 |
| Jimmy's Little Quest | Jairska | | No reviews. | 22 |
| Jimmy Caca's Quest | Jairska | | No reviews. | 29 |
| Joe Beans 1: Flight (GM's unreleased indev 001) | iamgreaser ◪ | 2010-06-17 | No reviews. | 75 |
| Jared 52 - Quantum Hell (ver. 1.1) | Giel ◪ | 2014-01-06 |
| 90 |
| Joe Beans in Flight | CJA / Greasemonkey / Kom | 2009-03-07 | No reviews. | 99 |
| Jello | CHEZZY ◪ | 2006-08-12 |
| 167 |
| Jonah Demo | Bramble ◪ | 2004-12-16 |
| 83 |
| Joey's World | Bluep4 ◪ | 2002-08-27 |
| 98 |
| Joey's World 2 | Bluep4 ◪ | 2002-09-20 |
| 107 |
| J.G. the Magician | Baby Bonnie Hood ◪ | 2015-02-09 |
| 129 |
| J.G.'s Mini RPG Thingy | Baby Bonnie Hood ◪ | 2012-02-24 |
| 127 |
| J.G.'s Neatsome Magical Adventures | Baby Bonnie Hood ◪ | 2011-04-30 |
| 189 |
| Joe and the Wandering Targets | acheron ◪ | |
| 102 |
| Julius Caesar | ???? | |
| 90 |
