Brewing Water Profile Calculator — UK Postcode Lookup
Brewing Water Profile Calculator
The ultimate UK homebrew water tool. Look up your water supplier by postcode, get typical chemistry values, then calculate exact mineral additions to hit the perfect profile for any beer style.
🏠 UK postcode lookup
🍺 14 beer style targets
💧 RO blending calculator
🧪 Mash pH predictor
⚙ Lactic acid additions
🖶 Printable brew sheet
Brew Day Water Sheet
Mineral Additions
Resulting Water Profile (ppm)
SO₄:Cl Ratio
Style Notes
Brew Day Checklist
☐ Weigh all minerals on 0.01g scale
☐ Measure water volume before adding
☐ Add gypsum & CaCl₂ to mash water
☐ Check mash pH at 10–15 min
☐ Adjust with lactic acid if needed
☐ Record actual pH reading
☐ Measure water volume before adding
☐ Add gypsum & CaCl₂ to mash water
☐ Check mash pH at 10–15 min
☐ Adjust with lactic acid if needed
☐ Record actual pH reading
Brew Day Notes
Write your notes here before printing…
🏠 Step 1 — Find Your Source Water
Enter your UK postcode to identify your water supplier. The link takes you to mytapwater.co.uk with your postcode pre-filled for an exact report.
⚠ These are typical regional averages. Click below for your exact postcode report.
Or select a classic profile / enter values manually (ppm)
💧 RO Blending Calculator
If source water ions exceed your target, dilute with RO water.
Blended profile
Load these values as your source water then continue to Step 2.
🍺 Step 2 — Target Beer Style
Select the style you’re brewing.
⚙ Step 3 — Calculate Additions
Click to see exact grams of each mineral salt to add. Your printable brew sheet is generated automatically.
Mineral additions for L
Resulting profile after additions
SO₄:Cl balance
Target profile —
✅ Brew sheet ready — scroll up or click to print.
🧪 Mash pH Predictor
Estimate your mash pH from water alkalinity and grain colour. Ideal range: 5.2–5.4.
Estimated mash pH
Estimate only. Measure with a calibrated pH meter.
🧪 Lactic Acid Calculator
Calculate ml of lactic acid needed to lower mash pH to your target.
Lactic acid to add
📈 Water Profile Reference Table
All 14 target profiles at a glance. Values in ppm.
📖 Brewing Water Chemistry Guide
Why it matters: Water is over 95% of your beer. Mineral content affects mash pH, enzyme activity, hop bitterness, yeast health, and overall flavour.
- Calcium (Ca): Enzyme activity and clarity. Target 50–150 ppm.
- Sulphate (SO₄): Hop dryness. 150–300 ppm for IPAs.
- Chloride (Cl): Malt fullness. 100–150 ppm for stouts and NEIPAs.
- Sodium (Na): Roundness. Salty above 150 ppm.
- Magnesium (Mg): Yeast nutrient 5–20 ppm. Sour above 40 ppm.
- Bicarbonate (HCO₃): Raises mash pH. Essential for dark beers.
Source exceeds target? Dilute with RO water — 50% RO halves all ion values.