pH Indicators | McMaster-Carr

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46 Products

pH Testing Paper

Check pH levels without a meter. When this testing paper is dipped in a sample, it changes color to indicate pH. Match the color of the testing paper to the color chart to determine the sample’s pH.

pH Range	Numeric Increments	No. of Color Points	Wd.	Lg., ft.		Each
0-13.0 pH	1	14	1/2"	50	0000000	000000
1.0-6.0 pH	1	6	1/4"	15	0000000	0000
1.0-11.0 pH	1	11	1/2"	50	0000000	00000
3.0-5.5 pH	0.5	6	1/2"	50	0000000	00000
3.0-9.0 pH	1	7	1/2"	50	0000000	00000
6.0-8.0 pH	0.4	7	1/2"	50	0000000	00000
6.5-13.0 pH	0.5	14	1/4"	15	000000	0000
8.0-9.5 pH	0.5	4	1/4"	15	0000000	0000
10.0-12.0 pH	0.5	5	1/4"	15	0000000	0000

Water-Quality Test Strips

Dip these strips into your liquid to quickly test water conditions. Strips change color to indicate the value reached; match the color of the strip to the color chart on the bottle to interpret the results.

Single-Substance Test Strips

For Testing	Range	No. of Strips		Each
pH	0.0 to 14.0 pH	100	00000000	000000
pH	0.0 to 6.0 pH	100	00000000	00000
pH	4.0 to 9.0 pH	50	00000000	00000
pH	6.5 to 13.0 pH	100	00000000	00000

5-in-1 Test Strips

For Testing	Range	No. of Strips		Each
Free Chlorine; Total Chlorine Total Alkalinity Total Hardness pH	1-10 ppm 0-240 ppm 0-25 gpg 6.2-8.4 pH	50	00000000	000000

Water-Quality Combination Test Kits

Test for contaminants before installing water-treatment equipment such as boilers and filters. You can also check your pipes and equipment for improper chemical levels that can cause corrosion and scale buildup, shortening their life.

340-test kits include tests for monitoring municipal water, which is often treated with chlorine.

Test Kits						Refill Chemicals
For Testing	Range	Test Type	Number of Tests		Each		Each
340-test kits
Total Hardness Iron Total Chlorine pH Total Dissolved Solids (TDS)	0-30 gpg 1-5 ppm 0.1-2.0 ppm 5 to 10 pH 0-9,990 ppm	Analog Analog Analog Analog Digital	120 50 50 120	0000000	0000000	0000000	000000

Water-Quality Test Kits

Analog

All the chemicals and labware you need for on-site sampling and water-quality testing.

Test Kits						Refill Chemicals
For Testing	Range	Test Type	No. of Tests		Each		Each
pH	3.0 to 10.5 pH	Analog	100	000000	000000	0000000	000000

Remote-Reading Multifunction Chemistry Meters

Take multiple water-chemistry and temperature measurements in hard-to-reach places from up to 3 feet away. Often used in tap water and wastewater, these meters work in both clean and dirty liquids. Automatic temperature compensation standardizes readings to 77° F to prevent inaccurate results in changing temperatures. The data hold function freezes the current reading on the display. For easy viewing, temperature and chemistry measurements appear on the same screen. These meters are IP57 rated, so they resist dust and withstand temporary submersion. They cannot be sold to Canada due to import regulations.

To maintain their accuracy, all have a calibration button and some also come with calibration solutions.

Conductivity, salinity, temperature, and total dissolved solids (TDS) meters take four measurements at once. Conductivity measures the concentration of salts, nutrients, chemicals, and other substances. Salinity measures the amount of dissolved salts. TDS determines the contaminant levels. The stainless steel sensor is durable and resists breaking.

Oxidation reduction potential (ORP), pH, and temperature meters take three measurements. ORP measures the amount of dissolved oxygen in liquids. It determines how efficiently a liquid breaks down contaminants.

For Testing Conductivity, Salinity, Temperature, and Total Dissolved Solids (TDS)

For Testing Conductivity, Salinity, Temperature, and Total Dissolved Solids (TDS)

Conductivity		Salinity			Total Dissolved Solids (TDS)
Range	Accuracy	Range	Accuracy	Temp. Accuracy	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Batteries Included	Cannot Be Sold To		Each
For Use With Clean and Dirty Liquids
0 to 19.99 µS 20 to 199.9 µS 200 to 1,999 µS 2 to 19.99 mS 20 to 199.9 mS	±1% ±1% ±1% ±1% ±1%	0 to 100 ppt	±1%	±0.9° F	0 to 0.1 ppm	±1%	32° F to 212°	Yes	Canada	0000000	0000000

For Testing Oxidation Reduction Potential (ORP), pH, and Temperature

Oxidation Reduction Potential (ORP)		pH
Range	Accuracy	Range	Accuracy	Temp. Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each
For Use With Clean and Dirty Liquids
-1,000 to 1,000 mV	±0.2%	0.0 to 14.0 pH	±0.01 pH	±0.9° F	32° F to 212°	IP57	CE Marked	Yes	Canada	0000000	0000000

Replacement Sensors

For Testing		Each
Conductivity, Salinity, Temperature, Total Dissolved Solids (TDS)	0000000	0000000
Oxidation Reduction Potential (ORP)	0000000	000000
pH	0000000	000000

Remote-Reading Multifunction Chemistry Meters with PC Output

Test temperature, chemical concentration, contamination, and salt levels in liquid from up to 6 ft. away, then send the results to your computer for analysis. These meters include a USB cable that transfers up to 1,000 readings. Often used to test water quality, they work on both clean and dirty liquids—from tap water to wastewater. Conductivity tests measure the concentration of salts, nutrients, chemicals, and other substances. Total dissolved solids (TDS) tests report contaminant levels. Salinity tests determine the salt levels in liquid. The sensor is made of stainless steel, so it’s durable and resists breaking. IP67 rated, these meters are dust tight and withstand temporary submersion.

To prevent inaccurate results from changing temperatures, these meters automatically standardize temperature readings at 77° F. Temperature readings appear on screen with other measurements, so you won’t have to scroll through multiple screens. A data hold function freezes the current reading on the display.

To maintain accuracy of the meters, they come with calibration solutions and have a calibration button.

These meters cannot be sold to Canada due to import regulations.

For Testing Conductivity, Resistivity, Salinity, Temperature, and Total Dissolved Solids (TDS)

Meter

Conductivity		Resistivity		Salinity			Total Dissolved Solids (TDS)
Range	Accuracy	Range	Accuracy	Range	Accuracy	Temp. Accuracy	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Batteries Included	Cannot Be Sold To		Each
For Use With Clean and Dirty Liquids
0 to 200 mS	±1.5%	0 to 20 megohms	±1.5%	0 to 100 ppt	±1.5%	±0.9° F	0 to 100 ppt	±0.1%	32° to 212°	Yes	Canada	00000000	0000000

Replacement Sensors

Replacement Sensor

For Testing		Each
Conductivity, Resistivity, Salinity, Temperature, Total Dissolved Solids (TDS)	00000000	0000000

Bench-Top Multifunction Chemistry Meters

Check the pH and conductivity of water and other clean liquids with one bench-top device. This meter has automatic temperature compensation that standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration knob to maintain accuracy.

Import regulations restrict sales to the listed areas.

Meters
	pH		Conductivity										Replacement Sensors
Sensor Material	Range	Accuracy	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, ° F	Ht.	Wd.	Dp.	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Glass	2-12 pH	±0.2 pH	0 to 10 µS 0 to 100 µS 0 to 1,000 µS 0 to 10,000 µS	±2%	50° to 160°	4"	3 1/2"	4 1/2"	Yes	Canada	00000000	0000000	00000000	0000000

Water-Resistant Multifunction Chemistry Meters

For Use with
Clean
Liquids

Test different water-chemistry measurements in dirty, wet conditions. Often used in pools and spas, all of these meters are for use with clean liquids. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a calibration solution (not included) and the calibration button to maintain accuracy.

IP57 meters are protected from dust and temporary submersion in liquids.

Chlorine, oxidation reduction potential (ORP), and pH meters come with three sensors that each take one chemistry measurement. They cannot be sold to Canada due to import regulations.

Import regulations restrict sales to the listed areas.

For Testing Chlorine, Oxidation Reduction Potential (ORP), and pH

For Use With Clean Liquids
Sensor Material	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each
Glass	23° F to 194°	IP57	CE Marked	Yes	Canada	0000000	0000000

Replacement Sensor for Testing pH	Each	000000
Replacement Sensor for Testing Chlorine	Each	000000
Replacement Sensor for Testing Oxidation Reduction Potential (ORP)	Each	00000

Easy-Read Bench-Top Multifunction Chemistry Meters

Don’t strain your eyes reading a scale—these bench-top meters indicate exact results on the digital display. For complete resistance to dust and protection from temporary submersion, these meters float and have a housing that meets NEMA 6 and IP67. They're for use with water and other clean liquids. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration button to maintain accuracy.

Import regulations restrict sales to the listed areas.

Meters									Replacement Sensors
For Testing	Sensor Material	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Conductivity, Oxidation Reduction Potential (ORP), pH, Resistivity, Total Dissolved Solids (TDS)	Glass	32° F to 160°	IP67, NEMA 6	CE Marked	Yes	Canada	000000	000000000	000000	0000000

Remote-Reading pH Meters with PC Output

Meter

LCD Display

Transmit pH readings to a PC for analysis. These meters have a sensor on a 6-ft. cable for taking remote readings of water and other clean liquids. They have automatic temperature compensation that standardizes readings at 77° F to prevent inaccurate readings in fluctuating temperatures. Use the included calibration solution and calibration button to maintain accuracy.

Import regulations restrict sales to the listed areas.

Meters
	pH								Replacement Sensors
Sensor Material	pH Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Nonglass	-2 to 16 pH	±0.01 pH	-22° F to 260°	CE Marked	Yes	Canada	00000000	0000000	000000000	0000000

pH Meters

More precise than test strips, these meters are often used to measure the pH of dirty liquids in agricultural systems, aquaculture tanks, and printing fountains. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a Calibration Solution (not included) and the calibration button to maintain accuracy. Meters cannot be sold to Canada due to import regulations.

	pH
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Batteries Included	Cannot Be Sold To		Each
For Use With Dirty Liquids
Glass	0 to 14 pH	±0.1 pH	32° to 122°	Yes	Canada	0000000	000000

Remote-Reading pH Meters

Monitor pH readings from your smartphone or tablet—download the app to view data up to 160 ft. away using Bluetooth. Made of durable nonglass, the sensor resists breaking. They are for use with dirty liquids, so they stand up to petrochemical, environmental, and agricultural testing. Rated IP67, they seal out dust and withstand temporary submersion. Use a calibration solution (not included) and the calibration setting in the app to maintain accuracy.

These meters cannot be sold to Canada due to import regulations.

Meters
	pH										Replacement Sensors		Calibration Solutions
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Data Connection Type	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each		Each
For Use With Dirty Liquids
Nonglass	0 to 14 pH	±0.02 pH	32° to 176°	Bluetooth	IP67	CE Marked	Yes	Canada	0000000	000000000	0000000	0000000	000000000	000000

Water-Resistant pH Meters

Check pH in harsh field conditions. These floating meters that have a housing that meets IP67 for complete resistance to dust and protection from temporary submersion. Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures. Use a calibration solution and the calibration button to maintain accuracy. They do not include Calibration Solution. Meters cannot be sold to Canada due to import regulations.

Meter for clean liquids is commonly used in pools and hydroponic solutions.

Meter for dirty liquids stands up to wastewater, plating bath solutions, and other harsh liquids.

Meters
	pH									Replacement Sensors
Sensor Material	Range	Accuracy	Automatic Temperature Compensation (ATC) Range, °F	Environmental Rating	Specifications Met	Batteries Included	Cannot Be Sold To		Each		Each
For Use With Clean Liquids
Glass	0 to 14 pH	±0.1 pH	32° to 122°	IP67	CE Marked	Yes	Canada	00000000	0000000	000000	00
For Use With Dirty Liquids
Glass	-2 to 16 pH	±0.01 pH	32° to 122°	IP67	CE Marked	Yes	Canada	00000000	000000	00000000	000000

Multifunction Chemistry Controllers

LCD Display

LED Display

The same controller can actuate equipment based on pH or oxidation reduction potential (ORP). Attach pH and ORP sensors (not included) and set the current measurement type with the selection switch. Controllers turn equipment on or off when the reading reaches the actuation point. They have one control relay and two alarm relays. Relays are SPDT (single pole, double throw) and can be set to turn one circuit from “off” to “on” (normally open) or from “on” to “off” (normally closed). Automatic temperature compensation standardizes readings at 77° F to prevent inaccurate results in fluctuating temperatures.

Controller with LED display is more visible in low-light conditions than controller with LCD display.

	pH		Oxidation Reduction Potential (ORP)
DIN Trade Size	Range	Accuracy	Range	Accuracy	AC Voltage (Phase)	Mount Type	Ht.	Wd.	Dp.	Fasteners Included		Each
LCD Display
1/4	0.0 to 14.0 pH	±0.01 pH	-1,999 to 1,999mV	±0.1%	120 (Single)	Panel	3 3/4"	3 3/4"	4 3/4"	No	00000000	0000000
LED Display
1/4	0.0 to 14.0 pH	±0.01 pH	-1,999 to 1,999mV	±0.1%	120 (Single)	Panel	3 3/4"	3 3/4"	4 3/4"	No	00000000	000000