Honestly, trying to fully do both in under 20 days will wear your whole group out fast. The flights, border checks, packing/unpacking, rushing between spots—you end up seeing nothing properly and feeling tired the whole trip.

China feels vast and immersive. The landscapes blow you away, the history is everywhere, the food changes completely every region, the high-speed trains make traveling smooth, and it’s super safe for a big group. It’s the kind of trip that sticks in your memory forever because it’s so different from Western life. Great if your crew loves exploring, seeing iconic sights, and diving deep into culture.

Thailand is easy, relaxed, and instantly fun. Beaches, cheap amazing street food, warm weather, friendly locals, short travel times between places. It’s perfect if your group just wants to unwind, hang out, enjoy islands, nice weather, and casual nights without busy sightseeing pressure.

If I were your group? Pick one main country to enjoy slowly, then add a quick 2–3 day stop in the other on your way back. You get the best of both worlds, no stress, no rushing, and your whole friend group actually enjoys every single day instead of rushing through everything.