pH Test Strips 0-14

I test my well water's pH. These test strips give consistent results. I cannot tell how accurate they are because I do not have a standard which to test the water's pH level and compare the results. I tested the water with a kit from a local home store that had only one pad on the strip for pH and got a 4.0 result. With these, I get a 6.5 pH reading. I tend to believe these test strips over the home store's test because one pad changing color is not very precise, and 4.0 is very low. A pH of 6.5 seems a lot more reasonable. These test strips have four pads for different ranges of pH, which is more accurate than looking at just one square.

I recently purchased several different ph test strips for my daughter to use for a science fair project. These are the absolute best and most accurate of the test strips I bought. They are as accurate as test strips can be. The colors don't run, unlike some of the others I tried. And they measure in increments of 0.5. They read what they should for the solutions I tested these with (a mixture of water and baking soda for a basic test, vinegar for an acid test, and Evian water for a neutral test since Evian is bottled to be consistently around a ph of 7.2). For those of you trying to use these or any strips to test ph of water, please be aware that all ph test strips will be inaccurate for *most* waters, unless you take special steps (see below). Most bottled water, as well as most tap water, is low ionic strength. Test strips for ph do not work well for low ionic strength liquids (even the ones that say for water). There are some exceptions. Mineral and artesian waters, such as Evian, are higher in ionic strength due to much higher levels of total dissolved solids. For these waters, ph test strips will work fine without altering the testing procedure, including those that indicate for saliva and urine testing only. Some reviews complain about accuracy due to testing with distilled water and not getting a reading of 7.0. Distilled water has nearly 0 total dissolved solids. No ph test strip will work under those conditions. Most mineral waters and artesian waters will tell you on the bottle what its ph is. E.g. Evian claims 7.2. These test strips give a reading of 7.0 in this case and you can't get closer with 0.5 increments. For these strips, or any strips, to work, the total dissolved solids must be greater than 150 ppm. Most mineral waters have at least 220 ppm total dissolved solids, and will have it listed on the bottle, which is why these test strips work in this case. If you need to test ph of low ionic strength waters, such as distilled, tap, most spring waters, then you'll probably need test drops or a meter instead. If you really want to try ph test strips for these waters, there are 2 things you can try. First, you can try soaking strip in water longer such as 30 to 60 seconds instead of 2 to 3 seconds. Second, and more effective, you can try dissolving a neutral salt to increase total dissolved solids. Potassium chloride KCl should work which you can purchase as a solution. Table salt, sodium chloride, should also work, but look for one that is plain salt without anti-caking ingredients and without iodine. Check the kosher salts wherever you buy groceries. Neutral salts won't change the ph of the water, but will increase total dissolved solids. Obviously don't drink the sample you test if you use this approach.

I used these to test the pH of several samples of river water for a school science project. They are a little tricky to read because the colors are so similar, but when compared to other pH strips I would say they are accurate enough. If you are looking for very accurate readings, I would purchase an electronic meter, but these are good enough for science projects and such.

I am using these PH strips to test PH of soaps and lotions I make. The stips themselves are stored in a small and rigid plastic container that is easy to open and get the strips out. I bought the single color ones before and felt like I was never sure if I was reading it correctly, and turns out I was not. The color difference seems a bit more obvious with these and I feel more confident about the result.

The colors on the color chart are so close, it's nearly impossible to get 0.5 accuracy. I would say more like plus or minus 1.0. These strips are not really any better than all the others advertised as 1.0 accuracy.