Group 24 Vs Group 27 Battery: What’s The Difference?

Batteries store energy and provide power for your vehicle, equipment, or device. They are commonly found in cars, trucks, motorcycles, boats, tractors, and other equipment or machine with a motor. We know that battery groups can be confusing, and a couple of examples are Group 24 and Group 27 batteries.

What are the differences between a Group 24 and Group 27 battery? One of the most common questions asked by people who work in the auto industry. The answer is that there are many differences, but they are not always obvious to someone who doesn’t know much about batteries. This article will go over some of these differences so you can make sure you’re using the right one for your car or truck.

Battery Group Size Chart

Battery Group Size Dimensions (Length x Width x Height) Cold Cranking Amps @ 0°F (-18°C) Reserve Capacity @ 25A BCI & IEC Standard
35 8.25 x 6.75 x 7.12 420 45 BCI & IEC
24 7.19 x 3.43 x 6.30 390 30 BCI & IEC
34/78 10.12 x 6.75 x 7.12 740 95 BCI & IEC
47/H5 7.19 x 5.12 x 7.13 320 50 BCI & IEC
75/65 10.02 x 6.80 x 9.41 640 110 BCI & IEC
65/85 10.02 x 6.80 x 9.41 750 130 BCI & IEC
94R/H7 7.19 x 5.12 x 7.13 520 70 BCI & IEC
35/78 8.25 x 6.75 x 7.12 450 50 BCI & IEC
75/95 10.02 x 6.80 x 9.41 850 145 BCI & IEC
86/H6 7.19 x 5.12 x 7.13 620 90 BCI & IEC
49/H8 7.19 x 5.12 x 7.13 420 60 BCI & IEC

What is the difference between a Group 24 and Group 27 battery?

Group 24 and 27 batteries are similar but not identical. When it comes to their dimensions, battery types, and chemistry, they’re almost the same; however, these similarities come with differences as well.

It’s important to know that these batteries are not exactly the same, and using them interchangeably is dangerous unless you’re certain the manufacturer would allow it.

The size difference between group 24 and 27 batteries is more than just a numbers game. While they may look similar, the groups have significant implications for their amperage rating.

When you are buying batteries, the labeling can be confusing. The group 27 battery is bigger than the group 24. An excellent tip to remember when shopping for your next set of batteries: If it doesn’t fit in your device or compartment, then obviously it won’t work.

Why is it essential to know the group batteries?

The group of batteries is an important descriptor of the battery. It positions the battery in a group that determines its chemistry and capacity.

As you can see, it’s not just a numbers game when differentiating between these two types, but rather worth knowing which one is best suited to your device or equipment.

When selecting a battery for your device, it’s important to know which type you need to get the most power out from your battery, and these group batteries can help you make the right choice.

Which battery group is better, group 24 or group 27?

Technically any battery will do the job, but it is important to understand how batteries are categorized and how they can perform in order to ensure that you are getting the service quality over your investment.

Group 27 batteries typically last longer than a Group 24 battery. As long as the requirement is compatible with a group 27, it will produce more amperage output than a group 24 battery. Group 27s also usually have an A in the rating (i.e., “27A”), which means that it includes “Automotive Grade.” Group 27 batteries are intended for use in heavy-duty commercial and industrial equipment. Because of their extra capacity, they also provide more power and last longer. If you are searching for a battery that will last the longest while maintaining long-term performance over years to come, Group 27 may be your best bet!

Most people know about group 24 batteries because those are what’s installed in most cars today. Group 24 batteries are not intended for high-current applications. However, some models feature a CCA rating of 500-840 Amps and an MCA (marine cranking amps) rating of 625-100 Amps, which allows them for use as starting batteries on smaller gas or diesel engines. They can be used for smaller devices like motorcycles or snowmobiles that do not require as much power output.


When selecting a new battery, be sure that it is the right one for your intended application. The two most important factors are size and terminal types – make sure they match up properly to ensure proper fitment. You also need to consider capacity, CCA/MCA rating, RC (reserve capacity) rating as these all play into how well you can use it in many situations, such as starting an engine or drawing down the voltage from a deep cycle battery.

Remember to be cautious as you use these batteries as they contain acid and can cause damage or injury if misused.

Understanding which group your battery is classified as will help you determine if it can be used to start your engine or power some of the other high current draw applications for which batteries are used. If these battery groups may seem confusing, you can ask an expert in this field for clarification, and that you’ll be able to get a better recommendation of which battery you need to achieve the most optimal results.

About the author, Phil Borges

Phil Borges is a battery aficionado. He's written extensively about batteries, and he loves nothing more than discussing the latest innovations in the industry. He has a deep understanding of how batteries work, and he's always on the lookout for new ways to improve their performance.