A quality multimeter gives you the readings you need quickly and accurately.
While a cheap, badly made multimeter will only give you inaccurate readings (and headaches).
But not all cheap multimeters are bad.
There are a few budget multimeters under $50 which give more accurate readings than other multimeters over $100.
These budget multimeters provide a lot of value – they’re just hard to find.
Well lucky for you – we’ve done the hard work for you. This in-depth review takes a look at some of the most popular multimeter brands available – including Fluke, Mastech, Klein, and Extech.
Whether you’re a beginner looking for a budget multimeter for home use, or a technician looking for a premium HVAC option for work – you’ve come to the right place.
- Precise readings – gives you the True RMS value
- Automatic AC/DC voltage selection with AutoVolt function
- Built-in non-contact voltage detector
- Accurate measurements on noisy HVAC equipment
- Built-in thermometer for temperature readings
- Lifetime Warranty
- 1 Fluke 117 Multimeter – Best Overall
- 2 Fluke 87-V Digital Multimeter – Premium Choice
- 3 Klein Tools MM400 – Great Value
- 4 Mastech MS8268 Digital Multimeter
- 5 Extech EX330 Multimeter
- 6 Greenlee DM-45 Multimeter
- 7 What is a Multimeter (or Multitester)?
- 8 Parts of a Multitester
- 9 Multimeter Symbols
- 10 How to Read a Multimeter
- 11 Types of Multimeters
- 12 What is a True RMS Multimeter
- 13 How to Test a Car Battery with a Multimeter
- 14 Who Invented the Multimeter?
Fluke 117 Multimeter – Best Overall
Let me put it simply: The Fluke 117 Multimeter is a work of art.
Anyone who has used this multimeter before will know exactly what I’m talking about.
It. Just. Works.
Fluke’s tagline for this multimeter is literally “The Ideal Multimeter for Electricians”. I was initially skeptical – I’m sure every company thinks that their multimeter is “Ideal”.
While that may be true, Fluke’s 117 multimeter stays true to its tagline.
Everything about this multimeter just screams quality. The crystal clear display. The LED backlight. The AutoVolt function (which autodetects AC/DC voltage for you). Its CAT III safety rating. Its intuitive and easy-to-use user interface. Its True RMS accuracy.
All the way down to the way it feels in your hand. Fluke have really outdone themselves on this one. There was clearly a lot and back and forth between electricians and the engineers at Fluke to produce this baby.
And unlike many competitors, Fluke are standing behind the quality of their devices. The Fluke 117 multimeter comes with a generous 3 year warranty.
Here’s a list of features that come with the Fluke 117:
- Measures resistance, continuity, frequency, and capacitance
- Provides Min/Max/Average to record signal fluctuations
- AutoVolt and low input impedance modes to provide faster, more accurate readings
- Features compact ergonomic design for one-handed operation
- A 3 year warranty
- CAT III 600 V safety rated
- A large white LED backlight to improve measurement visibility in poorly lit areas
- AutoVolt and low input impedance modes provide faster, more accurate readings
- VoltAlert™ technology for fast, go/no-go non-contact voltage detection
- Comes with a holster with probe holders for easy storage
The only downside to this multimeter is that it’s slightly pricier than some of the alternatives.
So if you’re looking the best budget multimeter under $50 – grab yourself a Klein Tools MM400.
But if you’re willing to spend a bit more, then the Fluke 117 Multimeter is well worth it. This is the perfect multimeter for electricians and electronics technicians.
Save yourself the headache – get a Fluke 117.Check Price
- Precise readings – gives you the True RMS value
- Crystal clear display with LED backlight – great for poorly lit areas
- Automatic AC/DC voltage selection with AutoVolt function
- Built-in non-contact voltage detector
- CAT III 600 V Safety Rated
- Not the cheapest on the market
Fluke 87-V Digital Multimeter – Premium Choice
When it comes to a HVAC multimeter – it’s better to pay for quality.
And with the Fluke 87-V Digital Multimeter, you won’t be left disappointed.
Fluke have used a custom-made low pass filter to provide accurate voltage and frequency measurements on Adjustable Speed Drives (ASD) and other electrically noisy equipment.
The Fluke 87-V is able to measure up to a huge 1000 V AC and DC and provides the True RMS voltage – essential for HVAC technicians.
Another great feature is the built-in thermometer. This allows you to make temperature measurements without a separate thermometer. This is an extremely handy feature which we really wish was included in some of the cheaper Fluke multimeters.
The Automatic Touch Hold is another one of this multimeter’s stand-out features. It captures stable readings without forcing you to press extra buttons while measuring.
The Fluke 87-V records Min/Max/Average and has a Min/Max alert that automatically captures variations. The Relative mode also removes test lead interference from low-ohms measurements.
Along with a sturdy holster and case, the design element on the multimeter has a recessed dial/raised case to help protect the selector and the screen.
To complement its case, the Fluke 87-V is well proportioned; from the protected jack inputs to the uncluttered selector dial.
The Fluke 87-V is the safest multimeter we reviewed. It has a Category IV safety rating up to 600V, and a Category III safety rating up to 1000V. It’s also been independently tested to comply with the second edition of ANSI/ISA S82.01 and EN61010-1.
The Fluke 87-V Digital Multimeter is the best premium multimeter on the market. We think Fluke know this – that’s why the Fluke 87-V comes with a Lifetime Warranty.
Although it’s a little pricey – we can understand why. It’s absolutely packed with features (and made in the USA).
But if you’re a HVAC technician or electrician who is looking for a multimeter to last a lifetime – then look no further than the Fluke 87-V Digital Multimeter.Check Price
- Accurate voltage and frequency measurements on noisy HVAC equipment
- Built-in thermometer gives temperature measurements without a separate thermometer
- Lifetime Warranty
- Measure up to 1000 V AC/DC
- Designed and built in the USA
- Pricey (but quality!)
Klein Tools MM400 – Great Value
Need a multimeter without breaking the bank? Then the Klein Tools MM400 is your best bet.
It has all the features you’ll need for conducting repairs, diagnosis, and measurements. The multimeter comes with a rubber holster, making it difficult to slip out of your hands.
The Klein Tools MM400 automatically sets the measurement range, instead of having to do it manually. Beginner electricians will love this option – and even experienced veterans will appreciate the convenience.
It measures current up to 10A and voltages up to 600 AV/DC. Plus, it can carry out its resistance test to 40MΩ and can run frequency, temperature, capacitance, continuity, and duty-cycle tests.
It has a large backlit LCD screen, making it easy to use in dark or low-light conditions.
It comes included with test leads, a thermocouple, an adapter, and batteries.
Klein have made it very easy to replace the batteries – you only need to remove one screw!
Includes test leads, thermocouple with adapter and batteries.
Durability isn’t an issue with the MM400. The tool is built to withstand 3.3 feet drops and withstand frequent usage on a job site.
And with a CAT III 600V Safety Rating, Klein have kept the focus on safety.
The Klein Tools MM400 is a great option for those on a budget.Check Price
- Best budget option – under $50
- Easy to use – great for beginners and electronics hobbyists
- Comes with test leads, a thermocouple, adapter and batteries
- Measures up to 600 V AC/DC Voltage
- Low battery indicator and easily accessible battery compartment
- Does not give True RMS voltage
Mastech MS8268 Digital Multimeter
At an extremely cheap price – you’ll find the Mastech MS8268 Multimeter.
While it’s cheaper, the Mastech multimeter simply isn’t as capable as the Klein Tools MM400 – which will provide you with better value for money (even if it’s a little more expensive).
For example, the Mastech multimeter is slower than a lot of competing tools. It takes a little longer to get a solid reading – and that time can add up.
The 15-minute auto-shutoff feature is also annoying, and it can interrupt you while you’re in the middle of a job.
All this said, if you’re looking for the cheapest multimeter around that is still reliable, the Mastech MS8268 can be a great option for you.
Mastech’s multimeter is best suited for beginners and electronics hobbyists who are looking for a cheap option to get started with.Check Price
- Much cheaper than the competition – under $50
- Surprisingly reliable for its price point
- Provides accurate readings at low voltages
- Great low cost option for beginners and electronics hobbyists
- The 15 minute auto-shutdown can be annoying on longer jobs
- Can sometimes take a while to get a reading
- Does not give True RMS voltage
Extech EX330 Multimeter
The Extech EX330 is a great pocket multimeter.
It’s intuitive and easy to use buttons and interface makes it a good budget option for beginners.
We were big fans of the “Max Hold” and “Data Hold” functions.
The Max Hold function allows you to capture the multimeter’s highest reading – and the display will even update each time a higher reading is reached.
The Data Hold function allows you to freeze the current display. This is great for when you need to hold the current reading while you review and take notes.
The capacitance option allows you to charge a capacitor with a known current and measure the resulting voltage when performing electrical troubleshooting.
The EX330 measures frequency between 0.001Hz to 10MHz for quick and easy diagnostics when testing circuits.
These are very useful features for electronics hobbyists.
The built-in non-contact AC Voltage Detector is very handy for home use.
It uses a combination of an audible beeper and red LED indicator lights to alert you to the presence of voltage when placed near live wires, outlets, and switches.
The EX330 multimeter from Extech is one of the more capable options on this list, and it is comparable to the MM400 from Klein Tools when it comes to its price.
Overall the Extech EX330 is a great pocket multimeter for beginners on a budget.Check Price
- Compact pocket multimeter
- Cheaper option – under $50
- Intuitive and easy to use (good for beginners)
- Autoranging functionality
- Max Hold function allows you to capture the multimeter‘s highest reading
- Display could be improved
- Does not give True RMS voltage
Greenlee DM-45 Multimeter
While the Greenlee DM-45 Multimeter may not be the worst multimeter on the market, it certainly isn’t a good one.
This model is full of problems that honestly shouldn’t exist at this price point.
Let’s start with the test leads: they suck. They are way too short for comfortable use, and just scream “low-quality”. They were clearly NOT built to last.
The display is also unusable. Not only does it lack a backlight making it impossible to use at night – but it’s even hard to see during the day!
If all of this wasn’t enough, the three-minute auto-off timer combined with the relatively long startup time will drive you insane.
Not worth it – even for home use. Skip it.Check Price
- Replaceable fuses
- Leads are low quality and too short for practical use
- The display lacks a proper backlight and is hard to read
- Infuriating auto-off coupled with a long boot time
What is a Multimeter (or Multitester)?
A multimeter, also known as a multitester or VOM (Volt-Ohm-Milliammeter), is an electronic measuring instrument used to measure various electrical parameters.
Multitesters are a standard diagnostic tool for technicians and electricians in the electrical & electronic industries (see our guide on the best tools for electricians).
A typical multitester can measure voltage, current, and resistance. More advanced (and expensive) multitesters can also measure other electrical characteristics.
Multimeters are classified as either digital multimeters or analog multimeters, depending on how the electrical characteristic is being read and displayed.
Multimeters can either be handheld multimeters, or bench-top multimeters (bench multimeters). You can get handheld and bench multimeters in both digital or analog form.
Want to know more? This guide will teach you everything you would want to know (and more) about a multitester.
Parts of a Multitester
The parts of a multitester are:
- A Scale
- A Needle or Pointer
- An Adjustment Screw
- A Zero Ohm Selector
- A Range Selector Knob
- Test Probes
This is how you read the value being measured.
For an analog multitester, this is a series of markings in a semicircle.
In the example above, voltage, current, and resistance can be displayed. Which value you are measuring depends on what port you plugged into on your analog multitester.
This is the needle-shaped rod that moves over the scale of a meter.
The needle pointer is mechanically connected to the moving coil. The value the pointer hovers over indicates the value being measured by the multitester.
Note that when there are multiple values being measured on the same scale, you’ll need to pay attention to which port the multitester is connected to. Match the port up with the value being measured.
Also known as the dial or infinity knob. This allows you to adjust the pointer to the zero position of the scale – usually with the help of a flat head screwdriver.
Fun fact: the name ‘infinity knob’ comes from the fact that at 0 voltage, you have ‘infinite resistance’ (as per Ohm’s law).
Zero-Ohm Adjustment Knob
The zero-ohm adjustment knob is used to calibrate the multitester when you want to measure the resistance of an object.
To make sure the multitester is calibrated correctly:
- Turn on the multitester
- Connect the metal tips of the two probes.
- Use the zero-ohm adjustment knob to adjust the needle to point to ‘0 ohms’ on the scale
And that’s it! Since you’re not putting anything between the two metal tips, you would expect the multitester to read a resistance value of zero. If that’s not the case – then you need to use the zero-ohm adjustment knob to calibrate the multitester to… zero ohms!
Range Selector Knob
Also known as a selector switch. This allows you to adjust the settings of the multitester.
Using this you can change what the multitester is measuring (e.g. voltage, current, or resistance), as well as the range of the measurement (e.g. volts or millivolts).
The range selector knob can be auto ranging, or manual ranging.
Auto ranging is much easier to work with. You simply adjust the dial to the symbol corresponding the the electrical parameter you want to measure. You connect the test probes and like magic – you have your measurement.
Manual ranging on the other hand is a little bit trickier. With manual ranging, you need adjust the dial so that the value its set to is higher than the maximum value you expect from your circuit.
Let’s run through an example. In the image above, the multitester measures current using a manual range setting. The setting values are:
- 400 µA
- 4 mA
- 40 mA
- 400 mA
- 10 A
So lets say I have a circuit where I expect the maximum current to be 300 mA. I now need to select the manual setting which is higher than my expected maximum current. Hence I should adjust the range selector switch to the 400 mA setting.
In another circuit where I expect a maximum current of 6 A, I would adjust the selector switch to the 10 A setting. Here the 400 mA setting would be too low, as 400 mA < 6 A (remembering that 6 A = 6000 mA).
The holes at the front of the multitester are known as ports. You need you plug your test probes into the appropriate ports to allow the multitester to measure the parameter that you’re interested in.
A test probe (or test lead) is an instrument used to connect a multitester to a Device Under Test (DUT).
Test probes are flexible, insulated wires. They are able to establish an electrical connection between a multitester and the DUT without exposing electrical workers to live conductive parts.
Red test probes connect to the positive terminal, and black test probes connect to the negative terminal.
Test probes can range from simple, strong, low cost devices to complex, expensive, and fragile.
For a simple handheld multitester, the strong low-cost test leads are usually sufficient.
Types of Probes
The types of probes include:
- Banana plug to Simple Test Probes
- Banana plug to Alligator Clips
- Banana plug to IC Hook
- Banana plug to Tweezers
Multitesters connect to a test probe through a ‘banana connector’ – like most pieces of electrical test equipment.
Test leads are flexible, insulated wires, which act as the conductor from the multimeter to the item being tested.
Each test probe will have a ‘banana plug’ (male connector) on the end of each wire. These banana plugs connect to the multitester’s ‘banana jack’ (female connector).
You can have any type of connector you want on the other end of the test probe – only one end has to be a banana plug.
There are many different types of test probes available for multitesters. Below are a few of the most common.
Banana Plug to Simple Test Probes
These are your standard test probes that come with most multimeters.
The probes have a plastic handle near the end of the wire. This allows you to safely hold and guide the probe to your test point without affecting the measurement.
The end of the wire is connected to a pointed metal tip. This is the part of the probe that makes contact with the DUT.
These test probes are robust and low cost. The biggest downside is that they are not hands-free – they require someone to be holding the test probes.
Banana Plug to Alligator Clips
Alligator clips are arguably your most versatile test probe as they are able to connect to a wide range of objects.
Alligator clips are great for connecting to thick wires or pins on a breadboard. Unlike the simple test probes, these are hands-free.
Banana Plug to IC Hooks
IC (Integrated Circuit) hooks grab onto wires, pins and leads of electronic parts.
Similar to alligator clips, IC hooks will stay attached to the piece of equipment you’re testing, allowing for hands-free operation.
IC hooks are less slightly convenient than alligator clips as they can not be added and removed quite as easily.
The advantage of an IC hook is a stronger connection to the DUT. They work best when connected to smaller ICs or legs of ICs.
Banana Plug to Tweezers
Tweezer test probes are generally more fragile and expensive than the other test probes mentioned above, but can still be useful in certain scenarios.
Tweezer test probes are used when working with very small DUT. In particular, they are ideal for working with Surface Mounted Devices (SMDs) – i.e. components that are mounted directly onto the surface of a Printed Circuit Board (PCB).
The following is an explanation of the most common multimeter symbols.
Placed on the top left corner on most multimeters, this button locks the measurement into place after you’ve taken it.null
It tells you the equipment’s or circuit’s frequency. This is usually placed above the AC voltage option.
The Ohms symbol is an upper case Omega letter. This is used to find the resistance reading.
This has a right arrow with a plus sign next to it. As you could have guessed, this tells you if you’re working with good or bad diodes.
This symbol has a V and three hyphens above it and one straight line above it.
The AC voltage symbol looks like an A with “a road” placed on top of it. It has an A with three dashes and a straight line above it.
How to Read a Multimeter
When reading a multimeter, every multimeter has these four main settings:
- Display: This is where you can see the measurements
- Ports: Plug-in probes (i.e. to test car batteries)
- Probes: Multimeters have two probes. Usually one is black and one is red.
- Selection knob: This tells you what you want to measure.
To read and measure the ohms resistance using a multimeter:
- Clip the test leads on the resistor leads
- Dial the multimeter to the estimated resistance range
- Read the value
If your multimeter gives you a 1, then you’ve guessed low for a value. Move the multimeter’s dial upward until it gives you a valid reading.
However, if it gives you a 0, then you’ve guessed too high. Move the dial downward until you get a valid reading. If you’re on the lowest range and still have a 0, whatever circuit you’re testing has a resistance too low for your multimeter to measure.
Note that this is only necessary if you do not have an autoranging multimeter. If you have an autoranging multimeter – it will do all this for you. Simple attach the test leads to the DUT (Device Under Test) and read the voltage/current/resistance from the screen.
Types of Multimeters
A typical multimeter (or multitester) can measure voltage, current, and resistance. When used in this way, a multimeter is known as:
- A voltmeter when used to measure voltage
- An ammeter when used to measure current
- An ohmmeter when used to measure resistance
More advanced (and expensive) multimeters can also measure other electrical characteristics, including:
- Capacitance (measured in farads)
- Conductance (measured in siemens)
- Duty cycle (measured as a percentage)
- Frequency (measured in hertz)
- Inductance (measured in henries)
- Temperature (measured in degrees Celsius or Fahrenheit. Note that an accompanying temperature test probe is needed – usually a thermocouple)
Multitesters are classified as analog or digital depending on how they interpret and display the electronic characteristic being measuring.
Multimeters come in two forms: handheld multimeters, and benchtop/bench multimeters. As multimeters are often carried around, handheld multimeters are more popular than bench multimeters.
Also known as an analog multitester or AMM. Analog multitesters typically use a galvanometer to display a voltage, current, or resistance reading. Some analog multitesters also use bar graphs, LCD or vacuum fluorescent displays.
Analog multitesters are the ‘old school’ multitester design. While they look cool, they are generally outclassed by digital multimeters.
This is because analog multitesters:
- Are harder to read (hence yielding a less accurate reading)
- Are easier to break (less robust)
- Suffer from parallax errors
A parallax error is a perceived difference in the position of an object when viewed from two different lines of sight.
This occurs when viewing an analog multitester from the side. For example when viewed from the left hand side, it will look like the analog multimeter is measuring a larger value than it actually is.
To avoid this issue, measurements from analog multimeters should only be read when directly facing the multimeter.
Digital Multimeter (DMM or DVOM)
Also known as a digital multitester, DMM (Digital MultiMeter) or DVOM (Digital Volt-Ohm Meter).
In a digital multimeter the original signal is sampled, buffered, and averaged to display the measured voltage. An amplifier with an electronically controlled gain preconditions the signal.
A digital multimeter displays the quantity measured as a number. This eliminates the measurement inaccuracies caused by parallax errors, and general human error from misinterpreting the exact position of the needle pointer.
Digital multimeters are superior to analog multimeters because:
- They are easier to read (less chance of misreporting values)
- They are more robust (less moving parts)
- You don’t need to fiddle with a zero-adjustment knob
- You can fix your readings to the screen
- Many digital multimeters come with auto-ranging (meaning you don’t need to know in advanced whether the circuit is AC or DC)
What is a True RMS Multimeter
A True RMS (Root Mean Square) multimeter is a type of multimeter that is able to accurately measure both sinusoidal and non-sinusoidal AC waveforms.
Other types of multimeters – such as an Average Responding Multimeter or Oscilloscope – are only able to measure sinusoidal AC waveforms.
There are two types of AC waveforms:
- Sinusoidal (sine) waves: Symmetrical transitions between circular peaks and valleys, without distortion. Sometimes known as Pure AC Waveforms.
- Non-sinusoidal waves: Waves that have irregular patterns such as pulse trains, square waves, sawtooth waves, angular waves, and spikes. Effectively any wave that is not a sinusoidal wave.
There has been a huge increase in non-sinusoidal waves in electrical and electronic circuits, for example:
- Variable-speed motor drives
- HVAC devices (Heating, Ventilation, and Air Conditioning)
- Solid-state environments
- Electronic ballasts
Unlike the smooth sine wave produced by a standard induction motor, these devices produce unsymmetrical AC waveforms. A true rms multimeter is needed in these instances to ensure the voltage and current measurements are accurate.
How to Test a Car Battery with a Multimeter
Want to know how to use your multimeter to test the voltage of your car battery, then the following procedure:
Step 1: Set Up The Multimeter
Stop your vehicle and make sure that the radio, lights, and ignition are off. Select the correct DC voltage position on the multimeter (Alternative: the 12 V setting if there’s a dedicated car battery testing range).
The DC voltage is indicated with a V and a short line and a dotted line underneath it. The AC voltage is used to check the main voltage of your home and has a wavy line after a V.
Once you’ve tested the battery’s connectivity, then it’s on to step 2.
Step 2: Read the Meter
Now that the battery is connected look at the multimeter to determine if it needs to be recharged. The multimeter will display the reading in volts, showing its charge quality (i.e. 12.0 volts = 25% charge).
Look at the following table:
|Voltage Rating||Charge Quality|
|12.6 Volts||Fully Charged|
|12.4 Volts||75% Charge|
|12.2 Volts||50% Charge|
|11.9 Volts and below||0%|
Step 3: Check The Results
Anything that’s below 75% or at 12.45V is a sign that your battery needs to be recharged. However, it doesn’t tell you the quality of the battery. If the battery is unable to hold a charge after recharging, chances are you have a dead battery.
Step 4: Recharge Your Battery
If your car battery is below 12.45V, recharge it. After it’s been recharged, perform the previous steps to see if your battery is at the 12.65 range. If not, then you should get it checked out before seeking a replacement.
Who Invented the Multimeter?
Before multimeters were invented, finding the right measurement was a huge problem. You’d need one tool to find out the amps, and another one to measure the ohms.
This was extremely time consuming – so much so that it drove people to seek better solutions.
Donald Macadie is the inventor of the world’s first multimeter. Macadie became dissatisfied with the need of carrying separate instruments for telecommunication circuits. So, Macadie created a multimeter that could measure volts, amperes (amps), and ohms.
The first multimeter was named the Avometer. The meter had precision resistors, a voltage meter, and a coil meter, as well as sockets and switches to select the range.