Where to catch Ditto

In Paldea (Scarlet & Violet)

• West Province (Area Three) — Walk
• West Province (Area Two) — Walk

In Hoenn (Ruby, Sapphire & Emerald)

• Desert Underpass — Walk

In Johto & Kanto (Gold, Silver & Crystal)

• Route 34 — Walk
• Route 35 — Walk

In Kanto (Red, Blue & Yellow)

• Cerulean Cave — Walk
• Pokémon Mansion — Walk
• Route 13 — Walk
• Route 14 — Walk
• Route 15 — Walk
• Route 23 — Walk

Ditto — full Pokédex entry