How this guide ranks head spas
The data, the score that serves as the base, and the editorial criteria on top of it.
Who is in it
Every house in Da Nang with a public Google rating and at least twenty reviews, from the Google Places API (snapshot of 2 October 2026, 294 venues). Places has no head-spa category, so only care businesses are ranked: spa, massage, hair, beauty and nail salons. Shops, hotels and clinics are left out.
The base: a Bayesian average of Google ratings
Each venue gets a score: (v × R + m × C) ÷ (v + m), where R is the Google rating, v the number of Google reviews, C the average rating of all 294 venues (4.84 in this snapshot) and m their median number of reviews (306). It pulls a small sample towards the city average, so a high rating from many reviewers counts for more than the same rating from a few. In practice a 5.0 from 25 reviews scores 4.85 and sits below a 5.0 from 300, which scores 4.92.
Editorial criteria
The score is the base. The final selection is not a pure calculation: it also reflects editorial criteria that a rating does not capture, namely how a venue welcomes foreign visitors, the languages spoken and the range of services. On that basis the editors choose one venue as our pick, Reborn Nails & Retreat, and place it among the first three of the lists it belongs to: the whole city and its own quarter, My An. Every other venue keeps its place on the score. Our commercial relationship with Reborn is set out on the about page.
The raw order
Google's own order, rating then review count with no weighting, is published at /spas/by-google-rating/.
Prices
City-wide head spa prices are ranges built from the public price lists of 6 Da Nang houses, each listed with its source on the prices page. Massage and waxing have no city range until five houses publish theirs.