Multimeters are used by electricians primarily to measure current, voltage, continuity and resistance. A reliable, quality meter with high input impedance is the electrician’s most important tool, but even a hobbyist can benefit greatly from a basic test meter where accuracy is not critical.
There’s a huge variety of multimeters on the market and many factors to consider, such as category rating, features and of course price. While you shouldn’t leave yourself short, you don’t need to go over the top either.
This site provides unbiased advice to help you research and choose which multimeter to buy. We cover the popular brands and models, with detailed descriptions of key features, specifications, and the pros and cons of a given device.
There are several well known brands that produce various classes of multimeter. Here are some of the most popular ones:
The Fluke Corporation is without a doubt the number one manufacturer today, and arguably since its inception. They are the default, go-to brand with a large amount of high quality testers for most tasks. Reliability, accuracy and attention to detail are all tenets of the Fluke brand, and they lead the way on innovation.
Fluke multimeters are also stylish and hard-wearing – tested to the nth degree at their onsite testing and calibration facility – and conform to rigid standards. They produce a long list of high quality digital multimeters (DMM), from good entry level units to super-accurate tools for the service technician.
Fluke also produces an impressive number of other measuring tools, including clamp meters, insulation testers and thermal image condition monitoring equipment.
Though Fluke has a budget in mind for a given product – as with any brand – the focus is on producing an item to exacting specs and then setting the price. As such, they are a premium manufacturer, with prices from around $130. Yes, they are expensive, relatively, but they last… my Fluke 75 (bought early 1990s) is still going!
Extech Instruments is another respected brand name of quality handheld test and measuring equipment. Although not quite as high spec, their multimeters are nonetheless reliable and innovative, often incorporating extra features and boasting a rugged quality. One of their most popular is the excellent EX330, a small meter with a big feature-set.
Amprobe has been inventing and manufacturing electrical test products for generations. They have one of the largest selection of multimeters and amp clamp meters in the market and are a good midrange alternative. Their specialty is amp clamps (since they invented them), but they also produce a wide variety of very useful multimeters for the HVAC technician as well as for other trades. The brilliant little PM55A pocket multimeter is a great tester for anyone.
Klein is a widely recognized, privately owned US firm that both manufactures durable hand tools and a range of multimeters. The Klein MM1000 Electricians Multimeter and more budget friendly Klein MM200 are among their most popular. They also produce low impedance DMMs, dedicated HVAC meters and electrical test kits.
Etekcity is an online retailer of consumer electronics products and offers a budget range of multimeters for around the $20 mark. Prices are low largely due to their online persona, which doesn’t necessarily mean their products suffer. The feature-packed mini MSR-P600 is a popular tester for both entry-level and experienced electricians. These meters are decent starters for trainees and as a backup for automotive engineers and electronics technicians.
Based out of Irvine, California, INNOVA Electronics (parent firm: Equus) produce multimeters and other diagnostic test tools mostly for the car servicing industry. They are not as high spec as Fluke, nor need to be, with less emphasis on mains current testing, ruggedness or overload protection.
Their well priced 3300 series of test meters is in the $15 to $50 range. The 3320 model is especially popular, with such features as auto ranging and dedicated battery ‘load’ check, perfect for diagnosing auto faults.
What to Look for in a Multimeter?
A DMM is an essential item for the electrician and non-electrician alike. The choice can seem overwhelming, but as long as you know the basics, it’ll be easier to pick the right meter.
They are not made equal. Although cheaper meters have come a long way over the past few years, it generally pays to dig deep as those with a higher dollar value have a better build quality, better protection and are more accurate.
This is essential for electricians and technicians working with mains voltage / current and who may need more features. Tradesmen in industry should stick to industrially-rated, CATIII or CATIV multimeters.
This would be overkill for the hobbyist, who may only need one for testing voltage, resistance, and continuity. Features like capacitance, frequency, temperature measurements and True RMS will not be necessary.
All multimeters can measure voltage, continuity and resistance. The ability to measure current is usually less pressing, but, as a point of reference, look at a CATII meter that at least has a milliamp range. The higher safety-rated CATIII and CATIV multimeters can usually measure AC and DC mains current continuously.
The following are essential features in a quality meter for the electrician. Many of these might not be necessary for basic home / vehicle diagnostics and may be taken as guidance.
This is the internal resistance of the actual testing circuit of the multimeter and is important. The higher the better, so it has a lesser affect on the overall results when measuring resistance in a given circuit.
Input Impedance should be at least 10 megohms (MΩ).
Up to 600V AC / DC, CATIII rated.
Should also have a millivolt (mV) range.
Up to 10A continuous AC / DC amps. Ideally there should be a separate fused circuit for amperage (A) and milliamp (mA) inputs – separate jack sockets. Fuses should be of the quick blow, non-destructive ‘HRC’ ceramic type.
Resistance input range should be up to 20 megohms (MΩ), which would be a requirement when testing circuit board components.
For when measuring breaks in circuits / wires, the unit should have an audible ‘beep’ with a quick-latch reaction time.
Not essential, but the higher the testing voltage, the better. Most multimeters have a 2V diode test, and, although okay most of the time, some diodes require a higher test voltage.
Aside from electronics, not essential, but should ideally extend to the nano-farad (nF) or even pico-farad (pF) range.
FREQUENCY / DUTY CYCLE
Not essential, but if needed, the higher the bandwidth range the better – 100KHz and up.
Rarely needed unless you are keen on electronics, though an oscilloscope would give a more accurate result. Some cheaper multimeter brands might include a transistor checker as a tempter to divert attention from its limited specs.
Stick to testers with auto ranging, which is usually standard nowadays. This means that you don’t need to manually select a range (such as up to 200V, or 20K ohms) as the meter will determine the right range for you and display the result automatically with the correct decimalization.
NOTE: be sure to check the auto ranging response time – really needs to be less than a second.
Manual Ranging pros & cons
With manual ranging, you might need to know a bit about electrics to get going, since you will have to select the right range level before you can measure a circuit correctly. Example: a 9V battery would be measured by selecting the 20V DC volts setting. Those with experience may prefer it, however, as reaction times are usually better. The compromise is to buy an auto-ranging multimeter with a disable ‘RANGE’ button that allows you to measure manually.
Further to auto ranging is AUTO-V. This setting will determine whether a circuit is AC or DC and display the result in its correct range. This is ideal when you’re not sure of the supply voltage type and will save potential damage to the multimeter.
Aside from electronics, most applications don’t need super accurate tolerance. Most of the budget, standard meters on the market today average around ±1-1.5% across the various input ranges (volts, amps, ohms, etc).
Budget doesn’t necessarily mean inaccurate, although a top branded 6000-count multimeter, such as Fluke’s 117, will typically have an accuracy rating inside of ±0.5% on DC volts.
Most cheaper meters average out the RMS value of the equivalent DC voltage when measuring AC voltage, but present their results based on a perfect sine wave. The reading will be accurate as long as the wave is uniform. If it is erratic or ‘changed’, such as when measuring an inverter output voltage, the reading could be out.
Seen on most professional multimeters, True RMS gives a more accurate AC reading when the sine waveform is obscure.
NOTE: on deciphering which multimeter is more accurate, RMS type is not something you need to be overly concerned about if merely wanting a meter for hobbies, homes and vehicles.
Multimeters are categorized, or rated — that is, what they can safely test. If starting out and diagnosing car electrical faults, for instance, you could use a CATI meter. Installation electricians would want at least a CATIII meter.
Category I (CATI)
These are best for electronics or other low voltage circuits, such as in vehicles. CATI multimeters should not be used to test a mains supply.
Category II (CATII)
Good for single phase mains, such as house socket outlets, lighting circuits, home appliances and power tools, for example.
Category III (CATIII)
Okay for testing single and low current three phase circuits, including motors, distribution boards, control panel boards, and sockets and switches, etc.
Category IV (CATIV)
Can accommodate higher current and voltage levels (to 1000V) and feature overload spike protection circuits. Good for testing service supply panels, heavy duty machinery, pump motors and so on.
If you are unsure, it is best to go with a higher category rating. Seasoned hobbyists might want to consider CATII, where HRC (High Rupture Capacity) fuses should be installed.
Price usually dictates quality, as of course does its category rating, feature-set and specifications. For instance, CATI meters built for testing basic, low-voltage circuits won’t be as robust as CATIV meters for three phase power circuits.
In many cases, you’d want a rugged testmeter that comes with shock protection in the form of a rubber holster. These are complimentary on Fluke meters, as well as other brands upwards of the $30 mark. Also, look for nicely made jack sockets with rubber shrouds protecting the terminals.
It is worth researching multimeter reviews which make note of the quality of the circuit board and components, as well as plastics used in the construction of the enclosure. Over-current and over voltage protection may be incorporated to protect the device, user and environment.
The quality of the display on a $30-$50 multimeter is typically quite good today, and is often backlit. Keep an eye on the refresh rate, though – how often the display updates. Higher end ones usually have higher refresh rates, a higher count and higher resolution. Newer meters often have a bar graph that will show fluctuations in real-time like an analog meter.
It is worth pointing out that many cheaper multimeters can lose their charge quite quickly and you might find yourself forever opening up the back replacing relatively expensive (9V, or 3V cell-type) batteries. Choose one with a battery life of at least 300hr (specified without backlight).
NOTE: auto shut-off conserves battery life and is an important, often overlooked feature.
Pay attention to how the battery is accessed. Having to open up the case to change the battery is not only a pain, but, on the cheap ones in particular, the screws can quickly strip their fixings. Multimeters with a separate battery compartment are much more user-friendly.
The test probes should be of the silicon insulated type, supple, of good gauge and incorporate protective finger guards – essential in mains test meters. Cheapo models are notorious for including cheap probes on short leads. If you are testing CATII and above, ensure you have a good set of leads to protect against shocks, or consider buying a replacement pair.
Which Multimeter Brand?
Professionals tend to shop by brand. Those looking for reliability will often go for Fluke as they have the reputation and prestige to deliver a sound product. Similarly, Gossen Metrawatt and Amprobe also produce high quality.
But do you really need high end? It depends what you’re doing. The likes of Extech, Klein Tools and Craftsman produce decent quality multimeters for standard electrical work. However, those testing three phase power in a humid factory environment would be better served, and safer, buying the best.
Price and Value for Money
Similarly, if price is a major consideration, at least go for a brand that has been around for a while and avoid generic brands. They may seem to have all the bells and whistles, but you could almost guarantee that the enclosure, circuit board components, specifications, functions, accuracy and overall reliability will be sub-par.
In time, these cheapos will let you down and can be darn right dangerous. Be dubious of $10 multimeters that are built for anything but light CATI use.
Reliability is important for troubleshooting anything from car batteries and socket outlets to control panel board faults. You could get a cheaper meter for low voltage testing, but be aware it might not have handy features like auto shut-off.
Digital vs Analog
Digital all the way! They both measure and display the same values, though digital multimeters employ square waveforms to analyze inputs, whereas analog multimeters use sine waves. Analog is old hat and really only beneficial for those measuring changing values and waveforms, such as inverter outputs.
Digital offers many pluses. Most of all they are more accurate, easy to read and display precise values. They are also more robust to bangs as well as overloads, such as when testing under the wrong input range. Digital multimeters also generally offer more functions.
Although they are often cheaper, analog models can be unreliable as they are less accurately read at distance. In addition, they tend to have lower input impedance, meaning their very measuring of resistance in a given circuit might throw off the result. Digital meters tend to have high input impedance, which is especially important when testing electronic circuitry.
Where analog excels is in measuring fluctuating voltage, current or resistance, but bear in mind that a basic oscilloscope will give a more accurate reading. In addition, the better digital meters now have fairly reliable bar graphs displays.
I’m Still None the Wiser!
If you’ve read this far, are totally flummoxed and still don’t know which multimeter to choose, don’t worry, just bear these few pointers in mind before buying.
What’s it for: electronics, car diagnostics, DIY / home electrical maintenance, HVAC, industry?
The Bottom Line
Most people are looking for a basic multimeter to find out if a socket outlet has voltage, to test a battery or to find a broken wire in a power tool, etc. In this instance, you won’t need the accuracy and robustness of a high end device. Thus, consider starting with a cheaper, albeit brand name, model like the Etekcity MSR-R500, then perhaps upgrade later if you need more features.
If testing three phase voltage, and especially if measuring high current values, then it’s time for a serious tester such as a Fluke, Gossen or higher end Klein, which are safer and offer more reliability.