Comparison: Hong Kong vs Shanghai

No for both — under two separate regimes. Mainland China grants Japanese passports 30-day visa-free entry for tourism (verified July 2026, extendable once via the local PSB). Hong Kong runs its own immigration and gives Japanese passports 90 days. The 240-hour transit permit Western travelers navigate is irrelevant here — your 30-day exemption already covers it.

Shanghai — about 3 hours nonstop versus about 5 for Hong Kong. A 2–3 day weekend is realistic in Shanghai; Hong Kong wants 3–4 days to pay back the longer flight.

The hotel counter tells the story — 800–1,500 HKD a night in Hong Kong versus 300–600 CNY in Shanghai for the same mid-range tier, roughly twice the price. Mid-range daily budgets run 1,000–2,000 HKD versus 500–1,000 CNY. Local transport costs little in both.

Yes — and it can decide the trip. From Hong Kong, Shenzhen is 25 minutes by HSR from West Kowloon (Japanese passports enter under the same 30-day mainland rule) and Macau about 1 hour. From Shanghai, Suzhou is 30 minutes by HSR and Hangzhou 45–60 minutes (¥70–100).

Different strengths, both serious. Hong Kong is the Cantonese capital — dim sum, roast goose and top-tier Michelin density. Shanghai owns xiaolongbao and hairy crab and gathers all of China's regional kitchens. One meal to prove a point — dim sum in Hong Kong, xiaolongbao in Shanghai's Old City.

Shanghai — 2–3 days (the Bund, Pudong, Yu Garden, plus a Suzhou or water-town run). Hong Kong — 3–4 days (Victoria Harbour, the Peak, outlying islands, a Shenzhen or Macau hop). With 6–7 days you can fly between the two and do both.