A multimeter is a must-have tool for electricians. It can measure voltage current, resistance, capacitance and frequency easily. This makes it an essential tool for troubleshooting electrical problems. There are many different multimeters on the market, but the Klein MM300 is one of the most budget friendly options available. In this Klein tools mm300 multimeter Review, I will take a closer look at what this multimeter has to offer.

A Quick Overview

Why should you buy Klein MM300?

Klein MM300 is a great multimeter for electricians. It measures voltage, current and resistance very quickly. The backlit display makes it easy to read in dark conditions or when you’re wearing gloves. This meter does not have an auto-ranging feature but the manual ranges are clearly marked on the dial so that even if you are not familiar with multimeters, you can still use this one effectively. Read on how to test O2 sensor.


The Klein mm300 also has a built-in overload protection that will help to protect the meter and your circuit from damage. This is a great feature for those who are new to using multimeters. If you have a good budget then you can visit my list of best multimeters under $100.


The only downside of this meter is that it does not have auto-ranging features. This means that you will need to be a bit conscious while measuring values. But this is not much of a problem considering how affordable it is. Specially if you're a beginner, then it is the most recommended one.

Overall, this meter offers excellent value at such a low price point. It has everything you need for electrical troubleshooting.

Klein tools mm300 multimeter Review

Do you need a reliable multimeter that can measure up to 600 volts?

Klein is a trusted name in tools, and our MM300 multimeter is no exception. This meter is built tough to withstand a 3.3-foot drop, and it has an easily accessible battery compartment. Plus, it's priced right so you can get the quality you need without breaking the bank. If you’re looking for better options then I have also made a comparison of the Klein tools mm600 and mm700

With its large LCD screen, the MM300 makes reading measurements easy even in low light conditions. And because I want you to be safe while using this meter, it comes with overload protection and audible continuity detection. So if accuracy and safety are important to you, then the Klein MM300 is the perfect choice for your next multimeter purchase. Let's see it key features in detail.

Klein tools mm300 multimeter review

4.7/5 stars with 635 reviews


It comes with a bigger LCD display so you can see all your measured values in bigger fonts.

You can measure voltages of all AC DC electrical circuits up to 600V.

The meter has a tough build and can survive accidental falls from heights of up to 3 feet.

It has an easily accessible battery compartment for quick and easy battery changes.

The meter has an audible continuity detection that beeps when it finds a closed circuit.

It offers over-voltage protection from dangerous voltages.

It comes with a low battery indicator so you never get caught off guard by dead batteries again!

You can measure current from 200 micro-amps to 10A easily with this klein tools mm300 multimeter.

Resistance up to 20M ohm can be measured with this multimeter.

The meter has a CAT III 600V safety rating so you know it's safe for use around electricity.

It has a one year warranty, so if anything goes wrong with this meter in the first 12 months after purchase just replace it!

A separate car battery test option is also available in this meter ranging from 1.5VDC to 9VDC


In terms of its design, it fits well with its industrial applications. A outer silicon case makes it well insulated as well as slip proof. The dial is also sealed so that it can be used in dusty conditions. The rubber boot and holster make it durable for everyday use. This meter is rated CAT III 600V for use around live electricity.

  • It has an auto shutoff feature so you don't have to worry about leaving your meter on and draining the battery.
  • It has a tough build that can survive accidental falls.
  • Large LCD screen for easy reading even in low light conditions.
  • Overload protection fuses have been installed in it.
  • Affordable as compared to other multimeters of its league.
  • Does not have an auto-ranging feature.
  • You can not measure high currents with the Klein mm300. But Klein Tools offers budget friendly clamp meters like the Klein CL800 and CL900 for high current measurements.

What comes in the package?

1x Klein Tools MM300 Multimeter

1x Pair of CAT-III standard Test leads 

2x AA Battery Cells

How to use Klein tools mm300 multimeter - A Short guide

The Klein tools mm300 multimeter Review can only tell you about its features, not how to use it. But, It is very easy to use this multimeter. The multimeter has a dial for different measurements. You just have to select the type of measurement you want to take and it will show the result on its clear digital display.

Voltage measurement with Klien MM300

To measure voltage with this multimeter, you first have to ensure that the black lead is plugged into the COM port and the red lead is plugged into the VΩmA port. Now, touch the positive probe with phase and the negative probe with neutral to create a circuit. The meter will now show you the voltage reading. The same way you can measure DC voltage but you have to select the DC Voltage selection by rotating the dial.

Current measurement with Klein MM300

To measure current, you have to ensure that the black lead is plugged into the COM port and the red lead is plugged into the VΩmA port. Now, touch one probe of the meter with one conductor of the circuit and the other probe with another conductor of the circuit to create a complete circuit. The meter will now show you the current. 

I have also made a guide on how to check amps with a multimeter. Always keep in mind that you have to attach both test leads in series with load as shown in the picture.

how to measure current with Klein mm300 multimeter

Continuity test with Klein MM300

To do continuity test with Klein mm300, you have to ensure that the red lead is plugged into the VΩmA port and the black test lead into the (com). Now touch both probes of the meter with the two ends of a conductor or wire. If there is continuity between them then it will beep and if not, then it won't beep. But always make sure that the circuit is not energized. Otherwise your circuit or multimeter may damage.

Final verdict about Klein tools mm300 multimeter Review 

The Klein Tools MM300 is an excellent multimeter for electricians or electrical contractors. It's affordable and easy to use with all of its features clearly labeled so even a beginner can understand how it works without having any previous experience working on electronics before!

The only drawback we found was that there isn't really anything special about this particular model except for its price point: if you want something more advanced like an auto-ranging feature or True RMS functions then I have listed down the best budget multimeter for electronics work.

FAQs-Frequently Asked Questions

Are Klein multimeters any good?

Klein multimeters are generally considered to be of good quality. They have a reputation for being reliable and accurate, and they come with a variety of features that make them suitable for both professional and home use. Many professionals in the electrical field recommend Klein multimeters as one of their preferred brands.

Why is Klein MM300 multimeter cheaper?

Klein's MM300 multimeter is often less expensive than other Klein models due to its more basic features. It has all the necessary functions for most basic electrical tests and a large LCD display, making values easy to read at a glance. The MM300 is ideal for entry-level users who don't need any sophisticated features. However, it should be noted that the MM300 does not have as many features as other higher-end Klein models. Overall, Klein multimeters offer an excellent combination of quality, accuracy, and features at an affordable price.

Does Klein MM300 Multimeter have an auto-ranging feature?

  1. No, the Klein MM300 does not have an auto-ranging feature. It has a manual range setting with seven preset ranges for AC and DC voltage, current, resistance, continuity/diode testing, and frequency. It also has a Data Hold button to freeze readings and an Auto Power-Off feature to save battery life.