Whether you are replacing an existing unit or installing a new one, purchasing a garbage disposal is always plagued by the question, “What size do I need???”. Garbage disposals are a quick and easy solution when it comes to getting rid of food scraps. Choosing the right size, capacity and horsepower in your new disposal will allow it to operate efficiently and will save you time in the kitchen.

Take time when picking out your garbage disposal - you will be using it daily for many years to come!
This guide will walk you through what you need to consider when figuring out what size garbage disposal is best for your household
How To Choose The Right Size Garbage Disposal
A garbage disposal is a must have appliance as it saves you time spent in the kitchen by making cleanup quick and easy. All garbage disposals work in the same way, by shredding food waste into ground down particles so it can get washed down the drain and through the pipes. Choosing the best one however is can be a little tricky as there are so many choices available.
Things To Consider When Picking A Garbage Disposal
Determining Space Constraints
The first thing you need to do is break out your handy tape measure and measure how much space is available underneath your sink. Don’t forget to measure length, height, and width. Physical dimensions are important because a garbage disposal can consume quite a bit of physical space. Generally, the more powerful a garbage disposal is, the larger dimensions it has. If storage space is at a premium in your apartment or home and you need the space underneath your sink, then you will more than likely need to purchase a less powerful unit.

Which is right for you - a small, medium, or large disposal?
How Much Horsepower?
In the world of garbage disposals, size is determined by horsepower. Larger disposals tend to have more horsepower, and smaller ones have less HP. The benefit of choosing a higher horsepower means that not only will you will be able to grind down more types of food waste than a small, low horsepower disposal, but you will be able to grind down more of it in a shorter time.
Choose the situation below that is closest to yours to see what size garbage disposal you need and what makes and models are best:
If you live in a 3-4 person household, and your family cooks daily, your garbage disposer should have a minimum ½ horsepower motor. This will allow for quick processing of soft food wastes such as pasta, vegetables and fruits. Upgrade to ¾ HP if you want your disposal to be capable of handling harder to grind wastes like fruit peels and corn cobs - as well as the added benefit of running much more quietly during operation - brands to note would be Insinkerator's Evolution Compact, or Moen's Host series.
If you live in a 3-4 person household, and your family cooks daily, your garbage disposer should have a minimum of ¾ HP if you want your disposal to be capable of handling harder to grind wastes like fruit peels and corn cobs. Basic 3/4 Horse Power models to note are Insinkerator's Badger 5XP. At this horsepower level, premium garbage disposals can handle most types of waste while also operating much more quietly during operation - our favourites would be Insinkerator's Evolution Compact, or Moen's Host series.
If you live in a 5-7 person household, and your family cooks daily, your garbage disposer should have a minimum of ¾ HP to be able to handle large amounts of soft food waste at a time. A ¾ HP disposal can also handle everyday amounts of tougher wastes like fruit peels and corn cobs. Basic ¾ Horse Power models to note are Insinkerator's Badger 5XP. Upgrading to 1 horsepower however will mean a premium garbage disposal that handle all types of waste (except large bones) while also operating much more quietly during operation - brands to note would be Insinkerators Evolution Excel, or Moen's Chef Series.
For any households that have over 7 members, or if you wish to grind almost all food scraps (chicken, or fish bones, fruit and fruit pits included) a 1 to 2 HP model will be needed. Top choices would be Insinkerators Evolution Excel, or the Badger 1HP - both can handle pretty much all food wastes except for large bones, and the Evolution Excel has premium features such as noise reduction.
The more horsepower your garbage disposal has, the more food waste it can process at a time, and also the less you have to waste time picking out things it can't handle. A 1 HP garbage disposal can handle almost all food waste except large bones.
Of course, before buying any garbage disposal, you should always read the manufacturer’s recommendations for household size.
What Kind of Motor?
In addition to horsepower, garbage disposals are offered in two kinds of motor technology: permanent magnet or induction. If at all possible, avoid induction based motors in low horse power units - these have flywheels which spin slower and generate less torque or grinding power. This results in not only sub-par grinding performance, but also larger waste pieces being washed down the drain, leading to the potential for clogs.
In disposals with larger horsepower ratings, the difference between models with permanent magnet or induction based motors becomes less important, though permanent magnet based motors are still preferable due to their higher operating speed. Look for disposals that advertise a speed rating of 2100 RPM and above - these will be driven by permanent magnets.
Higher horsepower units may also use more power - it may be wise to check how many amps you have available before opting for a larger unit.
Bottom Line: Permanent Magnet Motors are Faster - reducing the chance of clogs and can dispose of more food scraps at a time.
If you are looking for a 1/3 horse power entry level disposal, check out our guide below, where we found the top 5 budget garbage disposal models that have permanent magnet based motors.

The Insinkerator Evolution Compact 3/4 Horsepower has great features and quiet operation
Materials & Construction
When choosing a garbage disposal, pay attention to what kind of materials make up the grind components (may also be listed as impeller, flywheel or shredder). The best materials are (listed from most durable to least durable) are:
- Alloy Stainless Steel - this is the strongest steel used in garbage disposal components - found in high end or commercial garbage disposals.
- Stainless Steel - the standard steel used in the majority of mid range garbage disposals.
- Galvanised Steel - used in lower cost disposals as it is not as hard as stainless steel and easier to manufacture.
- Cold Pressed or Rolled Steel - used in some lower end or no name brand disposals and should be avoided.
Grinding Chamber Size
The grinding chamber is where all the action takes place in the disposal - this is where the waste scraps are pulverised and shredded. The size of the chamber indicates how much waste the disposal can handle at a time. It is measured in ounces and in general you want a larger grinding chamber size, as it means you can grind down more food waste in a go. Smaller chamber sizes (under 26 Oz.) should be avoided if space allows.
- HOST SERIES: Designed for those who frequently cook for guests and need advanced cleanup power
- POWERFUL GRINDING: 2,700 RPM, ¾ horsepower Vortex motor provides fast, powerful grinding of tough food scraps and helps...
- CONTROLLED, SAFER GRINDING: Disposal only works when the batch feed stopper is engaged and locked into place, keeping...
Dishwasher Connection
Most garbage disposals will have a dishwasher connection at the back of the unit - if you have a dishwasher and intend to run it's waste water through the dishwasher, make sure the model you choose has this feature.
Switch Connection
There are several switch types available - if you have a previous installation you might want to consider keeping the current setup as modifying the switch may prove be more costly that the disposal itself. If you are installing a new switch, you can choose from an air switch or wireless switch (which prevents electric shocks) or the older style wall switch. There is also the toe-kick switch, which is also quite safe as it's activated with your foot.
Warranty
The warranty on garbage disposals is a good indicator of the build quality - short warranties (1 year) models should be avoided if possible. Some large, heavy duty disposals come with a 10 year or lifetime "we-come-to you" type of in-home warranty. If you are buying a disposal for your own home (vs. a rental) then a model with a longer warranty period may be a good investment.
High End Features
Some higher end disposals feature unique features such as sound insulation / reduction, automatic unjamming / auto reversing, and multiple grind chambers. These bells and whistles are great to have in a disposal, but do add to the cost. If your budget allows, a model with sound reduction is worth getting - especially if you have an open kitchen layout in your home.
- QUIET BUT POWERFUL: This innovative food waste disposal is the quietest disposal on the market, featuring advanced noise...
- DURABLE COMPONENTS FOR THE TOUGHEST FOOD SCRAPS: This garbage disposal features alloy stainless steel components with...
- AMERICA'S #1 DISPOSER BRAND: There are more American-built InSinkErator garbage disposals in US homes than all other...
Continuous Feed Or Batch Feed
Most disposals are continuous feed, meaning they stay running once you turn the switch on, and stay running until you switch them back off. Batch feed disposals are a consideration if you have young children, as it requires you to manually close the opening to the disposal before it will come on.
Reset Button And Allen Wrench Hole
Most garbage disposals will come with a allen key or hex wrench that is used to free up a disposal if it is jammed or if it's humming but not working properly. Some small budget models to not include this function making them harder to unjam. Also make sure your garbage disposal has a reset button (only the most spartan budget models do not include a reset button).
Flange / Kitchen Sink Connection Type & Material
The flange is a part that comes with the disposal that allows you to connect the disposal to the kitchen sink itself. This often overlooked part is responsible for many complaints when it comes to owning a garbage disposal - from leaking flanges to poor fitting flanges that cause noise and vibration. The best flanges are all steel construction. For quick installation, the EZ-Mount system is the fastest to install, but the flange itself may need to be replaced down the road as part of it is made of less durable plastic.
Frequently Asked Questions
Can I Install or Replace A Garbage Disposal Myself?
Most garbage disposals can be installed by yourself if you are a good DIY-er. This is especially true if you have an existing installation and you are just swapping out your old worn out or broken disposal for a new one, and you are not replacing the switch that controls the disposal. If you are installing it yourself, take accurate measurements of your plumbing setup. If you decide to hire a plumber, you should be able to have it installed for around $150, depending on your area (and your plumber).
What Size Drain Pipe Do I need For My Garbage Disposal?
Garbage disposals are designed to fit most common kitchen sinks, the drain pipe size needed is 3.5 - 4 inches. If you have a typical kitchen sink, it should fit.
That was a long read! If you can't decide which disposal is best for you, going with the crowd is usually a safe choice. Check out these top rated Garbage Disposals from Amazon:
- RELIABLE & EASY INSTALL: Badger Series disposers are a reliable & functional choice when affordability is the prime...
- DURABLE COMPONENTS: This garbage disposal features our exclusive 1/2 hp Dura-Drive Induction Motor and long lasting...
- AMERICA'S #1 DISPOSER BRAND: There are more American-built InSinkErator garbage disposals in US homes than all other...
- A MUST HAVE IN YOUR KITCHEN: This space-saving garbage disposal easily fits under your sink, perfect for small...
- LOW NOISE AND POWERFUL: This innovative food waste disposal features our exclusive 3/4 hp Dura-Drive Induction Motor...
- SAVE TIME AND ECO-FRIENDLY: From meal prep to cleanup, food waste disposal helps make it fast & easy to keep your...
- Size: 10.HIGH-SPEED MOTOR: The 1/2 HP, 2600 RPM (115v) permanent magnet motor jams less. Has dishwasher hookup
- EASY INSTALLATION AND CLEANING: EZ Mount for a quick and easy kitchen sink installation, removable splashguard for easy...
- 2 YEAR PROTECTION: 2-year Limited. Corrosion resistant grinding components
Last update on 2023-05-31 at 17:17 / Affiliate links / Images from Amazon Product Advertising API
Very helpful article
Thanks Jim!
Just what I needed to know. Thanks much????
I’m happy that I’ve found this blog. Full of helpful tips to homeowners who wanted to maintain and keep their plumbing system working for a long run. Also, an excellent guide for identifying what size is appropriate for your home.For other plumbing references and services in Oregon, Washington, and Las Vegas, make sure to drop by at Einstein Plumbing, Heating, and Cooling.
We love reading blogs like this, and we appreciate the work you put into your website and detailed information you provide. A great read and useful information!
Recently just installed one in my home during a kitchen remodel. Not that I am a plumber but I made my decisions based on some other criteria items as I only have two in my household now.
3/4 horses are typically quieter models then their 1/2 counterparts as they have more sound insulation due to the larger motor.
3/4 is the best bang for your buck if you want stainless internals.
3/4 models all came with better warranty then the 1/2 size
3/4 jam less
3/4 provide better performance thus decreasing chances of a smelling disposal.
3/4 does jump up in size under counter as they are not only a bit longer but they are also wider and the 3/4 does require downspout install on discharge side to the other trap to be assured the extra power doesn’t shoot water/food up the other sink drain. This makes the install a bit more challenging on a double sink as you plan out your disposal to trap tie in. (Depending on how your double sink p-trap lays out)
Disposal is an installed house appliance so I bought one for the size of my house not just how many people where in it. Mostly for the above reasons as well I do believe bigger is better.
i currently have a 1/3 h.p. disposal in my sink.it’s gone bad & i am thinking of upgrading to a 1/2 h.p. disposal. i live in a home with only 2 people.should i do this?
It’s great that you elaborated on the size garbage disposal. I believe that we should be responsible for having a proper garbage disposal for every home. And yes, we should know the size according to our need. Thanks for providing its basis.