Nintendo DS XL vs 3DS Game Compatibility: One-Way Only

They are incompatible. You cannot play 3DS games on a DS XL (or any DS/DSi). You can play DS games on a 3DS.

Compatibility Matrix

Game Format	DS / DS Lite	DSi / DSi XL	3DS / 3DS XL / 2DS
DS Cartridge (Black/Grey)	✅ Native	✅ Native	✅ Native (Backward Compatible)
DSi-Exclusive Cart (White)	❌	✅ Native	✅ Native
3DS Cartridge (White/Tab)	❌	❌	✅ Native

Hardware: 3DS has ARM11 CPU + PICA200 GPU. DS has ARM9/ARM7. Architecturally different
3D Screen: 3DS top screen is autostereoscopic; DS games render 2D only
DS Games on 3DS: Run in "DS Mode" (Underclocked CPU, disabled 3D, stretched to 400x240 or native 256x192 with black borders)
Save Data: DS saves on cart. 3DS saves on SD Card (Digital) or Cart (Physical 3DS)

Virtual Console: 3DS eShop (Closed March 2023) sold NES, GB, GBC, GBA, N64, DS (limited) titles. Not on DS/DSi.

Nintendo DS

Nintendo DS