What is the sulfate-to-chloride ratio?

It is the concentration of sulfate (SO4) divided by the concentration of chloride (Cl) in your brewing water, both in ppm. It strongly influences perceived balance: sulfate accentuates hop bitterness and dryness, while chloride accentuates malt fullness and sweetness.

What ratios suit different beers?

A ratio above roughly 2:1 is hop-forward (good for IPAs and bitters), around 1:1 is balanced, and below about 0.5:1 is malt-forward (good for stouts, milds, and malty lagers). These are guidelines, not hard rules.

How do I raise sulfate or chloride?

Gypsum (calcium sulfate) raises sulfate; calcium chloride raises chloride. Both also add calcium. Add small amounts, recalculate, and aim for total sulfate and chloride levels that suit the style, not just the ratio.

Is a higher ratio always more bitter?

Not exactly. The ratio shifts perceived balance toward dryness and hop crispness, but it does not change the actual IBU. Very high sulfate can also taste minerally or harsh, so extreme ratios are best avoided.

Does my water data leave my device?

No. The calculation runs entirely in your browser and nothing you enter is uploaded or stored.

Sulfate to Chloride Ratio Calculator

The Sulfate to Chloride Ratio Calculator turns two numbers from your water chemistry — sulfate and chloride — into the single ratio brewers use to dial in whether a beer drinks crisp and hoppy or full and malty. It then classifies the balance so you know which salt to reach for.

How it works

Sulfate (SO4) and chloride (Cl) are the two ions that most shape perceived balance in finished beer:

Sulfate sharpens hop bitterness and gives a drier, crisper finish.
Chloride rounds out malt, adding fullness and a sense of sweetness.

The ratio is simply:

SO4:Cl ratio = sulfate ppm ÷ chloride ppm

The calculator divides the two values and classifies the result:

ratio > 2.0      → hop-forward (IPAs, bitters, pales)
ratio 0.8 – 2.0  → balanced
ratio < 0.8      → malt-forward (stouts, milds, malty lagers)

(The 0.5:1 lower bound often quoted for very malty profiles falls inside this malt-forward band.)

Adjusting your water

To move the ratio, add the appropriate salt and recheck:

Add gypsum (calcium sulfate) to raise sulfate for hoppier beers.
Add calcium chloride to raise chloride for maltier beers.

Both also contribute calcium, which aids mash pH and yeast health. Aim for sensible absolute levels too — extremely high sulfate can taste harsh or minerally even at a “correct” ratio.

Example and notes

A West Coast IPA often targets something like 250 ppm sulfate to 75 ppm chloride, a ratio of about 3.3:1, emphasising a dry bitter finish. A malty Munich-style lager might run 50 ppm sulfate to 100 ppm chloride, a ratio of 0.5:1. Use the ratio as a flavour-balance guide alongside, not instead of, overall mineral levels and mash pH.