How to Check TDS Level & Ideal TDS for Drinking Water
Have you been hearing a lot about the TDS level in drinking water?
You must have.
Because that is what all the water purifier companies are talking about. That is one measure even consumers are talking about the most.
But, what exactly is this “TDS” and what is the ideal TDS for drinking water?
If you have no clue about what is the meaning of TDS in water, then you must read this post.
This post will provide you with all the details about
- What is the TDS level in water?
- How you can measure the TDS level?
- What is the ideal TDS level of drinking water?
TDS of Water Full Form
The full form of TDS in drinking water is “Total Dissolved Solids”.
What is TDS Level?
TDS level of water is the measure of all inorganic and organic substances that are dissolved in water.
The most common inorganic substances that are found in water are magnesium, calcium, and potassium.
To a certain degree, the presence of these minerals in the water is healthy, but when the level becomes too much, it is a cause for worry.
Most common constituents of TDS levels, like calcium, magnesium, etc., are generally harmless. But heavy metals like lead, mercury, arsenic, and fluoride can be really dangerous for your health.
Why Do You Need to Check TDS Level?
A study conducted by IIT Kharagpur revealed that almost 20% of India’s total land area has toxic levels of arsenic in its groundwater.
A significant number of Indians are drinking toxic water.
This is also evident from the data released by the Ministry of Jal Shakti in the reply to a question asked in Rajya Sabha on 1st August 2022. It was revealed that:
- Arsenic was found in around 209 districts in 25 states and UTs
- Uranium was found in parts of 152 districts across 18 states
- Lead was found in parts of 176 districts in 21 states.
- Iron was found in parts of 491 districts in 29 states and UTs
- Cadmium in parts of 29 districts in 11 states
- Chromium in parts of 62 districts in 16 states
Although TDS level does not tell you anything about the presence or absence of any of the contaminants that make up the TDS level.
But it gives you an initial idea of the overall quality of your drinking water.
And the best part is measuring the TDS level is very easy, as you’ll see below. So, there are no excuses for not knowing the TDS level of the water your family drinks.
A high TDS level (above 500 mg/l) indicates that the water quality is not good and you should not drink such water without purification.
Apart from the TDS level, there are around 50 other individual contaminants.
A thorough investigation of drinking water quality is only possible at a drinking water testing lab.
How to Check the TDS Level of Water at Home?
There are several methods for measuring the TDS level of water.
Below we have provided step-by-step tutorials on how to find the TDS level of water at home with and without using a TDS meter.
Method 1: Using Digital TDS Meter
The easiest way to find the TDS level of water at home is by using a digital TDS meter.
A digital TDS meter is an affordable, small, and easy-to-use device.
Use a digital TDS meter to check the performance of your RO water purifier, test the water quality, check for hardness, and ensure that you are drinking clean water.
Digital TDS meters are widely available in all the leading online stores in India and you can easily buy a quality Digital TDS Meter from Amazon.in for a few hundred rupees.
Here is how you can use a digital TDS meter to measure the TDS Level of water:
- Remove the protective cap.
- Turn the TDS meter on. You will find the ON/OFF switch is on the panel.
- Immerse the meter into the water up to the maximum immersion level (2 inches).
- Gently stir the meter to dislodge any air bubbles.
- Wait till the reading stabilizes (approximately, 10 seconds).
- Press the HOLD button and take it out of the water to view the reading.
- If the meter displays the ‘x10’ symbol, it means that you have to multiply the reading by 10.
- After use, shake off the excess water from your meter and replace the cap.
Watch this video on how to measure the TDS level in drinking water.
Precaution:
- Do not dip the meter beyond 2 inches because the meter is not watertight.
- Do not store the meter in places of high temperature or where direct sunlight comes.
Method 2: Using Filter Paper and a Scale
This conventional method was used before the invention of digital TDS meters.
We do not suggest using this method now as it requires a lot of time and effort. The final results are also not very highly reliable and the whole process is prone to error.
What are the things that you need?
- A sterilized beaker.
- A sample of water (tap water or rainwater) in the beaker.
- Filter paper.
- An evaporating dish.
- A stirring stick.
- A pipette that is large enough to collect a water sample of 50ml.
- A scale to measure.
Now, follow the instructions:
Step 1 – Weigh the evaporating dish in milligrams and make sure that the dish is empty, and free from any kind of particles. Note this measurement as “A” and come back to it after all the steps have been completed.
Step 2 – Take the stirring stick and vigorously stir the sample of water in the sterilized beaker. You need to agitate the liquid so that the particulate matter present in the beaker gets evenly distributed.
Step 3 – Take the pipette and collect 50ml of the stirred water. Please note that even while collecting the water, you have to continue stirring the liquid.
Step 4 – Extract water from the pipette and pass it on to the filter paper 3 times. There will be some sediment left behind in the filter paper.
Step 5 – If you see any particles in the filter paper, transfer them to the evaporating dish.
Step 6 – Wait for the filtrate (particles) to completely dry.
Step 7 – Once the filtrate on the evaporating dish is dry, weigh the evaporating dish again (with the filtrate) and call it “B”.
Step 8 – Measure the TDS level by subtracting B from A.
To check TDS level, use the formula: TDS = [(A-B)*1000]/ml
In this formula, A stands for the weight of the evaporating dish + filtrate, and B stands for the weight of the evaporating dish. Since 50ml was the quantity that you took in the pipette, the value of “ml” in this case will be 50. The final value of the dissolved solid is going to be measured in mg/L.
Precaution:
- Carefully weigh the evaporating dish and also, the weight of the evaporating dish with the filtrate.
- Wait for the filtrate or particles to completely dry before proceeding.
Most people often confuse the TDS level with water hardness. High TDS levels do not always mean that the water is hard. If you want to find out the hardness level of water then you should perform a water hardness test.
What is the Ideal TDS Level of Drinking Water?
World Health Organization (WHO) report on TDS in drinking water points out that reliable data on possible health effects associated with TDS in drinking water is not available.
No health-based guideline value is proposed for the ideal TDS of drinking water. Because TDS in water can be high because of many factors, in areas where the TDS content of the water supply is very high, the individual constituents should be identified.
The presence of dissolved solids in water may affect its taste. The palatability (acceptable taste) of drinking water has been rated by panels of tasters about its TDS level as follows:
| TDS Level (mg/l) | Rating |
|---|---|
| Less than 300 | Excellent |
| 300-600 | Good |
| 600-900 | Fair |
| 900-1200 | Poor |
| Above 1200 | Unacceptable |
What is the maximum TDS level advised by the Indian Authorities?
The Bureau of Indian Standards (BIS) has set the acceptable limit of TDS in drinking water at 500 mg/L.
However, the standard also mentions that in case no alternative source of drinking water is available, then this acceptable limit can be relaxed to 2,000 mg/L.
The BIS water quality standards also mention that if the drinking water TDS is higher than 500 mg/L then this may result in a decrease in palatability (acceptable taste) and may cause gastrointestinal irritation.
Whether you get your water from a borewell, water tanker, or municipal tap, you must make sure that it meets the BIS water quality standards. If your drinking water’s TDS level exceeds 500 mg/L, we suggest that you do not drink that water.
Minimum TDS Level for Drinking Water
It is important to note that some of the dissolved minerals in water are useful for human health and therefore very low or zero TDS is also not recommended.
Reducing the TDS level to a very low value also affects the pH level of the water, which BIS specifies should be in the range of 6.5-8.5. Water with very low TDS will taste dull.
There is no official minimum TDS level for drinking water, but a TDS of at least 50-150 ppm is the accepted minimum level.
| TDS Level (mg/l) | Reasons for Acceptability/Non-acceptance |
|---|---|
| Less than 50 | Safe but not ideal. You may find the water tasteless as water with such a low TDS level does not contain the essential minerals. |
| 50-150 | Acceptable. However, a TDS level in the range of 80-150 is considered ideal. If you are using an RO water purifier then make sure the TDS level of purified water is not below 80 mg/L. |
| 150-250 | Not acceptable. Use an RO water purifier with a TDS controller or mineralizer. |
| 250-350 | Acceptable. Most urban Indian homes have access to water in this TDS range. |
| 350-500 | Acceptable. As per the BIS guidelines, a TDS level below 500 mg/L is acceptable. |
| 500-900 | Not acceptable. Use an RO water purifier with a TDS controller or mineralizer. |
| 900-1200 | Not acceptable. Use an RO water purifier with a TDS controller or mineralizer. |
| 1200-2000 | Not acceptable and not fit for drinking. Choose a RO water purifier that can purify water with up to 2000 mg/L. |
| Above 2000 | Do not drink. Most home water purifiers can’t purify water with a TDS level over 2000 mg/L. |
Check out the following link if you would like to learn more about how Total Dissolved Solids come in water and what is the effect of low or high TDS on your health.
TDS Level in Drinking Water – FAQs
Always remember that a high TDS does not necessarily mean that the water is unsafe for consumption. Sometimes it may be a bit odd in terms of taste, color, or smell. Ideally, the TDS for drinking water should be below 300 mg/liter and the maximum limit that is considered safe is 500 mg/liter.
If you are eager to find out how good or bad your drinking water is, then you should get your drinking water tested.
Water purifiers that come with reverse osmosis (RO) technology are a great solution to reduce high TDS levels in the water. These purifiers are built with cutting-edge technology to ensure that the TDS levels in water are reduced and that the water is safe for drinking. If you are planning to buy one, then you can check the latest range of RO water purifiers.
Click to read: Can Water Softeners Lower the TDS Level of Water?
With the help of a TDS meter, you can even check the longevity and functionality of the RO membrane and replace it, if need be.
Share this information with your friends and family to equip them with the knowledge needed for checking the TDS level in drinking water. If you know of any other way to measure TDS levels, please feel free to comment.
Excellent article.
Oh my gosh! This is the first website that I find in the entire Internet that is truthful and accurate. Thank you so much for writing this article, my family and I have been having some health issues which high I am contributing to our our own filter. Seems our our old filter is reading a TDS of 20 ppm. And everyone that I’ve talked to says that it is OK, even with a pH of 6.2. He was to say I have not believed them and I have now found your website and it confirms my suspicion. I am very disappointed with USA website as most if not all say that APPM 20 it’s OK and that a pH of 6.5 is OK also. My question to you would be my tap water hardness is 450 Ppm. And pH of the tapwater is 7.1. I have an RO filter that makes our water extremely acidic 6.2 and very low TDS 30 ppm. I seem to be stuck at both extremes. What do you recommend I buy or two to calls us. I’ve had people say to simply sprinkle Himalayan salt into my RO water but I prefer not to do that. I know that this article was written a very long time ago, so I hope that you’re still around!. Thank you!
There are several easy ways to increase the alkalinity or pH level of your drinking water. Please check out our detailed post on how to make alkaline water at home.
Is it possible that we can bring TDS from 8k-9k to 2k than we use RO for filtration? If yes than how?
My borewell water’s TDS level is 1020 ppm. So, I bought LG water purifier ww180EP. Purified water TDS level is 85 ppm, this is fine or not?
Yes it is possible. But the RO purifiers that are available for home use are not suitable for water with such a high level of TDS. You will have to check some industrial water purifiers. By the way what is the source of water that you are trying to purify? Because TDS level of 8,000 is extremely high.
Whats the min and max tds of drinking water
does it show the reading in µS/cm?
1 µS/cm = 1 ppm? please clarify
Yes, It shows reading in PPM.
What is the minimum and maximum acceptable tds level for drinking water?
I have checked tds in my home water supply with digital tds meter and it shows 260ppm but it taste so nuteral.
Please suggest the best tds level that taste good.
Thanks
Amit
Thanks for this beautiful guide. I wanted to check tds of my house water supply and you filter paper method was so convenient for me.
Happy to help you. Thanks for your comment.
Awesome Guide. I used 1st method at my home. Thanks for writing such an guide.
Very good guidelines.
Thank you so much.
Sir my TDs meter showing 027 PPM. What does that mean?
This means the TDS level of water is 27 PPM or mg/l.
Glad, we could help.
Thanks for stopping by.
Much needed information before purchasing the water purifier
Thanks once again..