How to Measure pH of Water

Among its many chemical properties, water, as a liquid and a solution (e.g., when it’s not 100% pure H20) has a few that are unique. Regardless of their pH (power of hydrogen) values, all solutions are acidic, basic, or neutral, with a pH range of 0-14. It represents the number of hydrogen ions or hydroxide ions present in a solution.

In acidic solutions, hydrogen ions are millions of times more abundant than in basic solutions (such as citric acid, with a pH of 2.2). Acidic solutions lack hydrogen ions, while basic solutions have millions of times more hydrogen ions (for example, bleach or oven cleaner at a pH of 13.5).

It is considered neutral when the pH measurement is 7. The ideal pH level for measuring water is 7, which is the same as its purity. It is relatively easy to measure water’s pH level. We will explain in this article how to measure pH of water easily in five different ways.

Why is it important to measure pH?

In the natural world, a substance’s pH level determines a lot of what happens internally and in its interactions with the outside world, including how it reacts when in contact with other substances. Human blood, for example, has a pH of between 7.35 and 7.45, and when this pH range is violated, vital functions can be affected, resulting in serious illness, death, and skin damage.

When we examine the pH of foods, we can determine whether they are safe to consume or not, since pH indicates whether the food is in good condition or whether it can be consumed without posing any health risks for human consumption. In the same way, determining the pH level of the substances used in different industrial processes, including textile dyeing, is critically important for ensuring the success of the processes and the quality of the products. Alkaline or basic items, such as sodium bicarbonate, bleaches, and ammonia, are the most suitable for cleaning and disinfecting. The pH of the liquid cleanser, with a pH of 14, makes it one of the most popular alkaline elements.

Moreover, all commercialization companies should be accredited, no matter what industry they work in or what type of products they produce. In quality control, pH scales are a critical component. As a result, they will be able to determine what qualities and properties the substance possesses for the function. Different elements or environments with the presence of hydrogen, in either a high or low concentration, are not suitable for the existence of life, due to their high or low acidity or alkalinity.

Pharmacological and cosmetic companies, for example, will be able to ensure long-term performance of their active principles by determining pH levels and stabilizing them before they are put into use, thus protecting their customers from severe skin reactions.

How to Measure the pH of Water

We have five ways to measure the pH of water. Let us look at them now!

Digital pH Meters

how to measure pH of water

Once upon a time, this type of meter was very expensive. Today, we know that Asian manufacturers have lowered prices so that they can be afforded by everyone. However, the most accurate and reliable devices are more expensive.

With their measure, they can differentiate by 0.1 point variations of pH. There is no complicated process involved in using it. It’s very simple, wait about a few seconds for the electrode to measure after putting it in the water. Once the measurement has been taken, simply rinse under running water. Be careful not to use osmosis or distilled water when rinsing.

A number of its models are attractive due to their ease of use, precision, and low cost. However, it is important to note that such a type of meter would need to be calibrated.

We will have to calibrate more frequently if we use the device frequently and require a high level of accuracy. The reliability of the model will determine how often we have to calibrate. We can determine if calibration is necessary by calibrating every one or two months. By comparing the calibration results with the actual calibration, we’ll be able to determine how frequently it needs to be calibrated.

A storage solution should be used for frequently used items, even if they are only kept for a month or two. A solution like this prevents the meter bulb, the sensor that performs the measurement, from degrading.

Test Paper or Strips

how to measure pH of water

A pH measurement using paper or a test strip is a common way to determine the pH from time to time. The pH level of the sample is determined by examining the color of the test strip or paper. Color is extracted from the container, compared with the scale, and gives us data about pH. You can find them in a variety of formats, according to the measurement range. Range 7 being closest to neutral is the most interesting one for us.

Because the strip format is composed of several colors for the same grade, the measurement obtained is less ambiguous. However, since the paper only comes in one color, it is more difficult to determine precisely what grade it is. Its color is usually an intermediate one among those obtained by placing it on the scale.

There are several types of reactive paper available, including strips and rolls. A smaller piece of paper can be measured with tweezers, which is a very comfortable and practical way to take measurements.

Reactive Liquid

how to measure pH of water

Using a small sample of water to be analyzeds another widely used test is based on color change. By adding a certain amount of reagent liquid used as a meter, you can produce this change in the color of the sample. A color scale comes with the reagent, and, as with the strips, it is compared. There are no differences in measurement quality. There is a significant difference between the reagent liquid and the reagent paper since the reagent liquid is able to turn a small sample of water into chemical waste. Due to its lack of precision, we have placed it in the last place since it is difficult to precisely measure pH within 0.5 degrees.

Using Litmus Papers

how to measure pH of water

Litmus papers work differently from pH papers and can only determine the acidity or basicity of a solution.

As a first step, add enough sample water to a clean container to completely submerge the litmus paper strips.

Second, briefly submerge one of the papers in the water container.

It is either red or blue on litmus paper. If dipped in a solution with basic components, red litmus paper turns blue. If acidic solutions are applied to blue litmus paper, the paper will turn red. The test will only work with acidic or basic solutions. Litmus papers colored red or blue will not react with an acidic or neutral solution with a pH of 7.

While it may seem counterintuitive, a pH of 6 is 10 times more acidic than water, and an 8 is 10 times more basic. When it comes to corrosion and corrosion, acidic solutions tend to be more corrosive than basic ones.

Testing the Ph of Water Without a Kit- Using a Red Cabbage

how to measure pH of water

Step 1:

Prepare a clear glass bowl by cutting up a red cabbage. Prepare separate kettles of boiling water. Cover red cabbage with this boiling water, then place it in a glass bowl. Mix it occasionally and allow it to sit for approximately 30 minutes.

Step 2:

The pigment molecules in the cabbage react chemically with the distilled water, altering its color. The liquid resulting from the boiling will be purplish-red in color. Drain it off. Use this solution to determine the pH.

Step 3:

Fill a separate clear glass with the resulting liquid. Afterward, in this, add a few drops of the pH indicator solution.

Step 4:

Now that the watercolor has changed, you will now be able to determine its acidity (pink or red), neutrality (purple), or alkalinity (blue, bluish-green, or greenish-yellow). To determine the numerical value on the pH scale, you can match this color to a color chart.

A pH scale has numbers ranging between 0 and 14. Making your own pH indicators can be done with various vegetables and fruits. Blueberries, turmeric, plums, onions, rose petals, apples, and grape skins are all good choices.

How to Reduce the pH of the Water?

It is hard water if the litmus paper turns blue. In the next section, we will see how to reduce the pH.

In deciding the pH reduction method, we will take into account the reduction process that is needed. For example, if you only want to clean the fish tank, the garden, or your hair, you can use some specific techniques. Instead, lowering the pH of a whole-house water supply or kitchen appliance supply might require other methods.

  • pH reduction in fish tanks and irrigation water: Pour a liter of water into a container with a small amount of sulfuric acid or phosphoric acid. Allow the acid to stand for several hours and use litmus paper to test. Achieve your desired pH by varying the amounts of water and acidifier. Alternatively, you can use lemon juice or white vinegar.
  • Care for your hair: Using a solution of 1 liter of water and 1/4 cup of vinegar, you can neutralize the effect of hard water. Despite vinegar containing acetic acid, the amount is only 5%, so it is safe to consume in the proportions indicated.
  • Faucets: When descaling or anti-scale filters are what you need, you can install them on some faucets at home or in the shower.
  • Jugs with descalers: These have yet to be proved to be effective. It has been shown in several studies that the water quality is the same or is worse when using a jug.
  • Treatment systems for water: The installation of a water purifier combined with a sediment filter or a reverse osmosis system can be combined with an activated carbon filter. By combining filtering power with carbon’s acidifying properties, activated carbon filters offer the best of both worlds. The reverse osmosis pump passes water through a membrane that filters all particles down to the smallest ones. It takes tap water and filters and purifies it before returning it to the user. It means you will have soft water to drink, cook with, or wash dishes and utensils with.


What is used to measure pH?

The pH meter is an electric instrument that measures hydrogen-ion activity in solutions (alkalinity or acidity). Generally talking, a pH meter consists of an electrode that responds to pH and a reference electrode that is invariable (which is called a reference electrode).

Is 9.5 pH water safe?

A pH of between 7 and 8.5 has not been shown to cause harm when consumed. Water can be bitter when its pH exceeds 8.5. (It’s interesting to note that human blood has a pH of 7.365.)

How can I test my pH without strips?

You will need to put a litmus paper in your urine stream once you’re ready. If you want to dip the paper into the urine, you can either pee into a small cup and then dip it in. Compare the color of your litmus paper directly with the color chart on the litmus paper and see if it matches the color chart on your paper.

Is water acidic or basic?

There is no acidity nor basicity to pure water; it is neutral. When something becomes acidic or basic, what triggers it? In an unbalanced system, this occurs when the hydroxyls and hydroniums are not in balance. A substance is acidic if its positively charged hydronium atoms outnumber its negatively charged hydroxyl atoms.

How do you adjust pH in water?

When adding materials to a liquid solution, allow them to soak in the water for a few hours to allow them to “steep.” To raise the pH, add lime, wood ash, or a specially formulated solution, and to lower the pH, add sulfur.


The above methods can be used to test the pH of water at home. To obtain the best readings from the pH meter, calibrate it at regular intervals. You should verify that pH values are equal and accurate by using any two of the above methods.

A lime treatment can raise the pH of water, while an acid treatment can reduce it. Vinegar is an excellent acid to use in this circumstance. After setting up fish tanks, many people tested and stabilized the pH of the water. This post provides some information regarding how to test pH at home. We hope this helpful information has helped you.

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