What Does Water Taste Like? What You're Really Tasting in a Glass

The Short Answer: What Water Tastes Like

Pure water tastes like almost nothing. What you taste in a glass of tap, well, or bottled water is what's dissolved in it: minerals the water picked up from rock and soil, the disinfectant your utility adds, and traces of metal from the pipes it traveled through. That's why water from two towns, or from a private well and a bottle, can taste completely different even when both are fine to drink.

Good drinking water usually tastes clean and a little crisp, with no smell and nothing that lingers. Water with very little dissolved in it tends to taste flat. Water carrying a lot of minerals or metal starts to taste salty, bitter, or metallic. Below, you'll find where each of those flavors comes from, the levels at which people typically notice them, and when a taste is worth doing something about.

Does Pure Water Have a Taste?

Hardly any, though research in mice suggests the taste system can detect water itself. In 2017, a Caltech team measured the taste nerves of mice and found they responded to the five basic tastes, sweet, sour, bitter, salty, and umami, and also to pure water. The response ran through the taste cells that sense sour flavors. When the researchers switched those cells on with light, thirsty mice kept licking a spout that delivered light instead of water, even though it did nothing for their thirst (Caltech).

Before anyone tells you water tastes sour, two cautions. The work was done in mice, and the researchers themselves questioned what those cells actually tell the brain, suggesting they may not be linked to the unpleasant sourness we perceive: mice avoid lemon juice, yet switching the cells on didn't produce that kind of avoidance. What the study does show is that sensing water is part of how the taste system works, separate from whatever flavor the water happens to carry. The flavor itself comes from what's in the glass.

What Gives Water Its Flavor

Nearly everything you can taste in drinking water falls into three groups: dissolved minerals, the disinfectant, and your plumbing.

Dissolved minerals

As water moves through the ground it dissolves calcium, magnesium, sodium, potassium, bicarbonate, chloride, sulfate, and nitrate. Together these are measured as total dissolved solids, or TDS, and they're a major reason one water tastes different from another. When the World Health Organization summarized taste-panel research, water under 300 mg/L of TDS was rated excellent, 300 to 600 mg/L good, 600 to 900 mg/L fair, 900 to 1,200 mg/L poor, and anything over 1,200 mg/L unacceptable (WHO).

Less isn't always better for taste. The same WHO review notes that water with extremely low TDS can also be unacceptable to drinkers because of its flat, insipid taste. That's the dull, empty flavor people describe in distilled water. If you own a TDS meter, our guide on how to use a TDS meter explains what the reading can and can't tell you.

The disinfectant your utility adds

Most city water is disinfected with chlorine or chloramine, and some of it is still in the water when it reaches your glass. WHO notes that chlorine is present in most disinfected drinking water at 0.2 to 1 mg/L, and people are sensitive to it. According to WHO, most individuals can taste chlorine or its by-products, such as chloramines, at concentrations below 5 mg/L, and some can pick it up at levels as low as 0.3 mg/L (WHO). That's the swimming-pool note many people notice first in tap water. It's a sign the water was disinfected, not a sign something went wrong, and it's also the easiest taste to remove at home. Our guide to removing chlorine from water compares the options.

Your pipes and plumbing

Water can also pick up flavor on the last stretch of its trip. EPA notes that corrosion of iron and copper can stain household fixtures and give water an objectionable metallic taste (EPA). A metallic taste together with blue-green stains in the sink points toward copper; our article on copper in drinking water covers what to check next.

Common Water Tastes and What Usually Causes Them

EPA keeps a short list of secondary drinking water standards, which it calls guidance for nuisance chemicals. They're non-mandatory guidelines, and EPA doesn't enforce them. Their purpose is to flag the substances that make water taste, smell, or look unpleasant, along with the level above which people commonly notice each one. It's the closest thing there is to an official decoder for tap water taste.

Levels in the table come from EPA's secondary standards, except the chlorine row, which comes from WHO. A reading below these levels doesn't mean you can't taste anything; sensitive tasters notice some substances sooner, and several of these can build up together. For specific flavors, we've written deeper guides on earthy or musty tap water, well water that smells like rotten eggs, and water that suddenly tastes salty, chalky, or metallic.

How Different Kinds of Water Tend to Taste

Once you know what creates flavor, the differences between common waters make sense:

• City tap water carries the local mineral mix plus a trace of disinfectant, so a faint chlorine note is normal.
• Private well water doesn't pass through a utility's treatment plant, so its flavor is mostly whatever the aquifer and your well system add. Depending on the ground, that can mean a mineral or chalky taste, metal from iron or manganese, or a sulfur smell.
• Spring and mineral water taste of their source. Two brands can taste nothing alike because their mineral content differs.
• Distilled, reverse osmosis, and other purified water have had most of their dissolved solids removed, which is why they often taste flat on their own.

When a Taste Is Worth Checking

A taste you've always had is usually just your water's mineral signature. A change is different. Pay attention when:

• The taste or smell changes suddenly. City customers can start with their utility's annual water quality report; here's how to read your water quality report. Well owners should test, because nobody else does it for them.
• A metallic taste comes with stains or discolored water. Rusty color points toward iron, and blue-green stains point toward copper, both in EPA's list above.
• You're relying on taste as a safety check. It isn't one. EPA puts it plainly for lead: since you can't see, taste, or smell lead dissolved in water, testing is the only sure way to know whether harmful amounts are present (EPA). Great-tasting water can still need a test, and testing your water at home is where to start.

How to Change the Way Your Water Tastes

Match the fix to the taste, and test first if you don't know what's causing it.

Chlorine, earthy, and musty tastes: activated carbon

Activated carbon is the standard tool for taste and odor. EPA describes it as commonly used in drinking water treatment to adsorb natural organic compounds, taste and odor compounds, and synthetic organic chemicals (EPA). For chlorine and earthy or musty flavors, a carbon filter at the kitchen tap is usually the first thing to try.

Salty and mineral-heavy tastes: reverse osmosis

Carbon isn't designed to take out dissolved salts, so salty or high-TDS water calls for reverse osmosis. For sodium in well water, University of Maryland Extension recommends reverse osmosis or distillation, typically installed to treat one faucet such as the kitchen sink (UMD Extension). If you like the idea of reverse osmosis but not the flat taste it can leave, a remineralization stage adds a controlled amount of minerals back; see how to remineralize reverse osmosis water and what reverse osmosis removes.

Metallic tastes: find the source first

A metallic taste can come from the water source or from your own pipes, and the right fix depends on which. Test before you buy anything, because treating the water won't stop a plumbing problem from coming back. If you see blue-green stains, start with the copper check in the plumbing section above, and compare your test results with the EPA levels in the table.