Water hardness by postcode in Denmark
Enter your postcode: we match it to the nearest city with published hardness data and show its value, unit and source.
How the search works
Every postcode is matched to the nearest of the 388 cities in Denmark for which a water supplier or regulator publishes hardness. Supply areas do not follow postcode boundaries, so the result is the figure of the nearest published supply. If the match is more than 15 km away we say so, and the annual water quality report of your own supplier is the better reference. Each city page names the source document and its date and, where the supplier publishes them, the values of each supply zone.
Danish waterworks report hardness in °dH; GEUS classes: soft < 8, medium hard 8–12, fairly hard 12–18, hard 18–30, very hard > 30 °dH. Most Danish tap water is groundwater and hard.
Regions
- Capital Region75 · 18.8 °dH
- Central Jutland90 · 11.7 °dH
- North Denmark49 · 10.8 °dH
- South Denmark102 · 13.2 °dH
- Zealand72 · 18 °dH
Largest cities in Denmark
| °dH | mg/L | ||
|---|---|---|---|
| Copenhagen | 17.6 | 314 | very hard |
| Århus | 17.6 | 314 | very hard |
| Odense | 15.3 | 273 | very hard |
| Aalborg | 13.5 | 241 | very hard |
| Frederiksberg | 17 | 303 | very hard |
| Esbjerg | 6.8 | 121 | hard |
| Randers | 12.3 | 220 | very hard |
| Kolding | 10.9 | 195 | very hard |
| Horsens | 15.4 | 275 | very hard |
| Vejle | 13.4 | 239 | very hard |
| Hvidovre | 20 | 357 | very hard |
| Roskilde | 20.7 | 370 | very hard |
| Herning | 8.1 | 145 | hard |
| Silkeborg | 3.6 | 64 | moderately hard |
| Hørsholm | 19 | 340 | very hard |
| Greve | 21.5 | 384 | very hard |
| Hedensted | 11.7 | 209 | very hard |
| Næstved | 16.3 | 292 | very hard |
| Viborg | 8.1 | 145 | hard |
| Fredericia | 11.9 | 212 | very hard |
| Rødovre | 21 | 375 | very hard |
| Ballerup | 20.2 | 361 | very hard |
| Charlottenlund | 19.6 | 350 | very hard |
| Køge | 20.4 | 364 | very hard |
| Hillerød | 14.6 | 261 | very hard |
| Taastrup | 23.6 | 421 | very hard |
| Helsingør | 14.7 | 262 | very hard |
| Holstebro | 10.3 | 184 | very hard |
| Slagelse | 16.1 | 287 | very hard |
| Viby | 17.3 | 309 | very hard |
| Albertslund | 22.4 | 400 | very hard |
| Holbæk | 15.5 | 277 | very hard |
| Sønderborg | 15.8 | 282 | very hard |
| Svendborg | 16.7 | 298 | very hard |
| Allerød | 17.1 | 305 | very hard |
| Hjørring | 13 | 232 | very hard |
| Nørresundby | 12.8 | 229 | very hard |
| Glostrup | 20.1 | 360 | very hard |
| Ringsted | 17.7 | 316 | very hard |
| Frederikshavn | 9 | 161 | hard |