What Is ORP in Water?

Cut an apple. Leave it on the counter.

In twenty minutes it turns brown. Leave an iron gate out in the monsoon and it rusts. Nobody is surprised by either.

What surprises people is this: the same force has a number. And that number is in your drinking water. Every day. Nobody has ever shown it to you.

The number is called ORP.

What is ORP in water?

ORP means Oxidation Reduction Potential. It is measured in millivolts — mV.

In plain language: it tells you whether water takes electrons or gives them.

Positive ORP water is an electron taker. It oxidises. Same force that browns the apple and rusts the gate.

Negative ORP water is an electron giver. That is what an antioxidant actually is. Not a marketing word. A chemical behaviour.

Three numbers describe your water. Most people know one.

• TDS tells you how much is dissolved in it.
• pH tells you if it is acidic or alkaline.
• ORP tells you what it does.

Why does everyone check TDS but nobody checks ORP?

Because TDS is the number India was taught.

When RO arrived, "low TDS" came to mean "safe water." A whole generation learned to judge water by that one figure. Fair enough. Safety had to come first.

But TDS describes what is in the water. It says nothing about what the water does once it is inside you.

Two glasses can show the same TDS and behave in opposite directions. One oxidising. One giving.

The number that catches that difference is the one nobody sells you a meter for.

What does a positive ORP mean?

It means the water pulls electrons from whatever it touches.

Higher number, stronger pull.

Here is the uncomfortable part. Almost every glass of water in India reads positive. Municipal tap. Borewell. The 20-litre jar. The RO under your counter.

Tap and RO water in India typically read around +200 mV.

Your RO did its job. It made the water safe. Safe and ORP are two different questions.

What is a good ORP for drinking water?

Negative.

Water produced by electrolysis reads down to −800 mV. The Somawa Modish goes to −1000 mV.

Be precise about what that means. A negative ORP describes the water in the glass. It means the water arrives with electrons to give, not a deficit to fill. That is the mechanism. We describe it and let it stand.

Waters like the Hunza Valley's have been measured carrying a negative charge. Nature restructured that water. You just don't live on a mountain.

Typical ORP readings

Read the table again.

It is not that some waters score a little better. Everything ordinary sits on one side of zero. Ionized water sits on the other.

Does negative ORP water stay negative?

No. And this matters.

A negative ORP is not stamped into water like a mineral. It is a state. States relax.

Water made at −800 mV drifts back towards positive over hours. Air. Light. Time.

So negative ORP is a property of fresh water. Not shelf water.

Water ionized in a factory, sealed in plastic, trucked across a state, stored for three months — that water is not delivering what it measured on day one. That is not an attack on anyone. That is chemistry. Chemistry does not read labels.

A machine at your tap is a different proposition from a bottle. One makes the water seconds before you drink it. The other asks time to do it no harm. Time never agrees.

Is ORP the same as pH?

No. People confuse these constantly.

pH is a position — where water sits between acidic and alkaline.

ORP is a direction — which way it pushes.

An ionizer moves both, because the same electrolysis does both. But they answer different questions.

pH tells you what the water is. ORP tells you what it does.

A home that measures only TDS knows neither.

How do you measure your water's ORP?

With an ORP meter. A handheld probe. Same family as the TDS pen you probably already own. Dip it in the glass. The number appears in seconds.

You can buy one for about ₹500.

Or you don't have to. A proper test reads TDS, pH and ORP together — at your tap, in fifteen minutes.

This matters because water is local. Your city's supply. Your building's tank. Your RO's age. Your neighbour's number is not your number.

At Somawa, we measure before we talk. Our ionizers are incubated under NRDC — Ministry of Science & Technology, Government of India. But the report doesn't argue for us. The numbers do.

You do not have to believe us. You can measure it.

So what do you do with the number?

Know it. That is all, for now.

Most people who ask for a test are not shopping for a machine. They want the truth about a glass they have been drinking for years. That is the right instinct. Measure first. Decide after.

If your reading comes back positive — and it will — you now know something about your own water that most of the country does not.

Where you go next is not urgent. Water has been shaping bodies for a long time. It can wait a week while you think.

Want to know what your RO leaves out? Read: What Your RO Removes — Including What It Shouldn't. Want the engineering? The science behind your water.

It takes ten minutes at your kitchen tap. And you don't even have to buy the meter.

Individual experience. Outcomes vary by person, condition, and lifestyle. Somawa products are wellness devices, not medical treatments.