Hardest and softest tap water in Finland
All 76 cities in Finland with published data, ranked by total hardness. The national median is 3.5 °dH.
Finnish waterworks report hardness in °dH; most supplies are soft.
25 cities with the hardest water
| # | °dH | mg/L | ||
|---|---|---|---|---|
| 1 | Korsholm | 9 | 160 | hard |
| 2 | Kemi | 7.5 | 134 | hard |
| 3 | Ulvila | 7.3 | 130 | hard |
| 4 | Uusikaupunki | 7.3 | 130 | hard |
| 5 | Rauma | 7.1 | 127 | hard |
| 6 | Tornio · Lapland | 6.7 | 120 | hard |
| 7 | Jakobstad · Ostrobothnia | 6.2 | 110 | moderately hard |
| 8 | Kokkola · 16 | 6.2 | 110 | moderately hard |
| 9 | Forssa | 6 | 107 | moderately hard |
| 10 | Nurmijärvi · 01 | 5.1 | 92 | moderately hard |
| 11 | Eura | 5.1 | 91 | moderately hard |
| 12 | Vaasa | 5 | 90 | moderately hard |
| 13 | Klaukkala · Uusimaa | 4.9 | 88 | moderately hard |
| 14 | Vihti | 4.9 | 88 | moderately hard |
| 15 | Kiiminki | 4.8 | 86 | moderately hard |
| 16 | Raasepori | 4.6 | 83 | moderately hard |
| 17 | Salo | 4.5 | 80 | moderately hard |
| 18 | Pedersöre | 4.5 | 80 | moderately hard |
| 19 | Imatra · South Karelia | 4.5 | 80 | moderately hard |
| 20 | Kirkkonummi | 4.4 | 79 | moderately hard |
| 21 | Ii | 4.4 | 79 | moderately hard |
| 22 | Hyvinkää · 01 | 4.2 | 75 | moderately hard |
| 23 | Janakkala | 4.2 | 75 | moderately hard |
| 24 | Tuusula · 01 | 4.2 | 75 | moderately hard |
| 25 | Lohja · 01 | 4.1 | 73 | moderately hard |
25 cities with the softest water
| # | °dH | mg/L | ||
|---|---|---|---|---|
| 1 | Lieksa | 0.6 | 10 | soft |
| 2 | Kauhajoki | 1.1 | 20 | soft |
| 3 | Hollola · Päijät-Häme | 1.8 | 33 | soft |
| 4 | Kajaani · 18 | 2 | 35 | soft |
| 5 | Liperi | 2.1 | 38 | soft |
| 6 | Pieksämäki | 2.2 | 39 | soft |
| 7 | Kalajoki | 2.2 | 40 | soft |
| 8 | Lieto · Southwest Finland | 2.5 | 45 | soft |
| 9 | Alavus | 2.5 | 45 | soft |
| 10 | Kaarina · 02 | 2.5 | 45 | soft |
| 11 | Ylöjärvi · 06 | 2.5 | 46 | soft |
| 12 | Ylivieska | 2.6 | 46 | soft |
| 13 | Varkaus | 2.7 | 48 | soft |
| 14 | Haukipudas | 2.7 | 48 | soft |
| 15 | Loimaa | 2.7 | 49 | soft |
| 16 | Kankaanpää | 2.7 | 49 | soft |
| 17 | Hamina | 2.7 | 49 | soft |
| 18 | Porvoo | 2.8 | 50 | soft |
| 19 | Kotka | 2.8 | 50 | soft |
| 20 | Jyväskylä | 2.8 | 50 | soft |
| 21 | Raisio · 02 | 2.9 | 51 | soft |
| 22 | Lappeenranta | 2.9 | 51 | soft |
| 23 | Turku | 2.9 | 52 | soft |
| 24 | Naantali · Southwest Finland | 2.9 | 52 | soft |
| 25 | Lahti | 3 | 53 | soft |