These are cheat codes which can be accessed by inputting button sequences or by various other methods.
- Green Hill Zone: Get all 180 Emblems and unlock the 3D version of Green Hill Zone from Sonic The Hedgehog 1.
- Hidden Secretary Theme: When you are on the Theme Select screen, rotate the Control Stick Clockwise for a while until you hear a chime-like sound. You should be able to select the Secretary Theme.
- Last Stage: In order to play the actual last and final stage of this game, then finish both Hero and Dark side story games. Once this is done, go into story mode and a Last Stage? menu selection should appear between the Hero and the Dark Side selections.
- More Karts: Complete every mission for each story character (ranking does not matter) and you'll unlock the new kart for them. Simply highlight their picture on the select screen and press .
- Scene Select.: Beat the story mode.
- Alternate Costumes: Complete every mission for each story character with an "A" rank, and you'll unlock the new costume for them. Simply highlight their picture on the select screen and press .
- 1P Kart Race: Complete either Route 101 (Hero) or Route 280 (Dark) to unlock Kart Race in single-player mode.
- 2P Kart Race: Simply complete both Route 101 (Hero) and Route 280 (Dark) and Kart Race in 2P Battle will become available.
- Dark Boss Attack: Beat the game with the Dark Side to unlock Boss Attack in 1P Play. Boss Attack is basically a Time Attack to see how quickly you can beat all bosses on the Dark Side.
- Hero Boss Attack: Beat the game with the Hero Side to unlock Boss Attack in 1P Play.
- All Boss Attack: Beat all three main stories to unlock Boss Attack in 1P Play. This mode combines the Hero, Dark, and Last bosses.
- Level 4 2-player games: Beat Final Rush or Final Chase in the Hero or Dark side and the level 4 stage you beat should appear in 2-player mode.
- Hero Chao Garden: Raise a Hero Chao with one of the three Hero characters. Continually feed and train your Hero Chao and it should evolve (creates a tear-shaped cocoon). Once it evolves, ascending stairs should appear at the main Chao lobby leading to the Hero Garden.
- Dark Chao Garden: Raise a Dark Chao with one of the three Dark characters. Continually feed and train your Dark Chao and soon it will evolve (creates a tear-shaped cocoon). Once it evolves, the descending stairs should appear at the main Chao lobby.
- Diamond & Onyx Chao Races: Win at least one race from Aquamarine, Garnet, Peridot, and Topaz Chao Races to unlock them.
- Jewel races: Complete all 4 of the original races and get the emblem. The Jewel races will be unlocked.
- Super Level on Chao Karate: Complete all three of the original difficulties in Chao Karate using the same Chao and that Chao (and that Chao only) will now have access to a Super level.
- Ball for Dark Garden: Win the first 2 levels of the Dark race.
- Ball for Hero Garden: Win the first 2 levels of the Hero race.
- Ball for Normal Garden: Win the first 4 levels of the Challenge race.
- Broom: Win all 5 levels of the Topaz race.
- Car: Win all 3 levels of the Mushroom Forest race.
- Chao TV: Win all 12 Challenge Races.
- Jack in the Box for Normal Garden: Win the first 8 challenge races.
- Note in a bottle: Win all 5 levels of the Diamond race.
- Pencil Case: Win all 5 levels of the Onyx race.
- Picture Book: Win all 5 levels of the Peridot race.
- Pogo Stick: Win all 5 levels of the Garnet race.
- Radio for Dark Garden: Win all 4 Dark Races.
- Rattle: Win all 3 levels of the Block Canyon Race.
- Rocking Horse for Hero Garden: Win all 4 Hero Races.
- Shovel: Win all 3 levels of the Crab Pool race.
- Sonic Cuddly Toy: Win all 5 levels of the Aquamarine race.
- Watering Can: Win all 3 levels of the Stump Valley race.
- Shovel Chao Toy: Win all 3 Crab Pool races.
- Toy Car Chao Toy: Win all 3 Mushroom Forest races.
- Watering Can Chao Toy: Win all 3 Stump Valley races.
- Rattle Chao Toy: Win all 3 Block Canyon races.
|E218-M32Q-P0K83 + 0WT9-U5RK-V5A8G
|UH4Y-D0GG-25401 + GPXR-NJFJ-84GB7
|1YJR-345J-FJEJ2 + YUDC-RP89-0TJAD
|DXTT-EV4R-2HBTH + CXET-DXP3-GHEM0
||Always Low Time
|D882-TXUG-AFXK5 + GNE6-FU80-UA9JJ
|MGAG-5XJK-Y030W + JGMN-RDX9-RP939 + D00X-WAFP-U43PY + 9VPW-ZY86-9NMRE + D00X-WAFP-U43PY
||Tons of Emblems
|8TRX-PEBP-DM9PQ + XG2Q-7CQ2-V9X3Q + MF08-0RXW-WDJ18
||Hold for Super Turbo
|D2J0-TH29-Y2ETT + RXCE-EYFB-RR206 + URT2-VXZC-RCNZA
||Hold + for Super Jump
|4GVT-TQ13-49VH9 + ABZU-UNZ9-ZU2ZC + NEGX-44BW-ZV035 + 78WG-2F3Y-HN9QR + UYDC-9DE3-RPJTY + E9FZ-A3QA-YCERP
||D-Pad for Huge Size
|7GMW-H871-RH25N + MKAR-H3PM-RFKJU + XENX-7YKF-3TAWQ + PP4U-FF53-5931B + EA79-CAAH-6UFZX + E9FZ-A3QA-YCERP
||D-Pad for Mini Size
|R8X1-2RBP-C7JKK + D7VB-7672-W3KGD + HE3F-B1K7-UU9YN + H8JN-QWBE-1B9G6 + V11Z-262Z-6AV50 + E9FZ-A3QA-YCERP
||D-Pad for Normal Size
|YW0G-P8PK-E3VU6 + HC9Z-EFEH-9Z8DC
||Have Chao Garden Key
|ONLY USE THE FOLLOWING AT THE VERY END OF THE LEVEL BEFORE JUMPING INTO THE GOAL
|PBVG-KPU2-KVY72 + 6T2Y-DTNC-BFZBF + 6QUW-D10G-472RH + DYFD-E6W1-1AQED + U1YP-ZZ8K-ZV226 + E9FZ-A3QA-YCERP
|| + for Chao Set 1
|UUX6-A321-FKG66 + 4B0X-CERW-Y39JR + 6QUW-D10G-472RH + QU7P-VU4X-7FGJW +U1YP-ZZ8K-ZV226 + E9FZ-A3QA-YCERP
|| + + for Chao Set 2
|EUN1-PED6-1RFZ4 + 5EXR-RRTY-KFBUB + 6QUW-D10G-472RH + FPJC-1UP3-PG5PB + 8WPX-14KQ-JJQP1 + E9FZ-A3QA-YCERP
|| + + for Chao Set 3
|7V85-EB5E-T1K7W + G1HQ-DBYC-PVZAY + 3NV3-R6FU-ZPNDA
|19B3-825Q-2DXHQ + RDP2-Z7Z6-ZPDXB + WQYC-E3M9-1QVDR
||Press Z+X for noclip (hold X to move up and down)