All You Need to Know About Lawn Mower Deck Sizes

I was looking for a new lawn mower and have a lot of ornamental areas in my yard. I need a lawn mower that will fit in between these trees and knew I needed a deck size under 60 inches.

I found manufacturers will list deck cutting width, but they don’t always tell you how wide the actual mower is with and without the discharge chute. 

A mower listed as 60 inches usually means the deck cuts 60 inches in width, but the actual measurements are wider.

I definitely needed to know the actual width to be able to mow between these obstacles. I had to make sure it fits into my storage shed opening. Read on and I will explain more about measuring mower the mower deck size and standard deck sizes available by the manufacturer.

This post may include affiliate links. Purchases made through these links may provide a commission for us, at no extra cost to you. As an Amazon Associate, we earn from qualifying purchases.

Follow all safety instructions provided in your equipment operator’s manual prior to diagnosing, repairing, or operating.Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.

What is the Deck Size on a Lawn Mower?

Lawn mower manufacturers always list the deck sizes on their websites and promotional materials. What are they measuring when they list the mower deck width?

The mower deck width manufacturers are referring to is the cutting width of the deck.  The deck cutting width is the actual width of grass that is cut from the outside blade of one side of the mower deck to the outside blade on the opposite end of the mower deck.

How to Measure Lawn Mower Deck Size?

It is good to know what the cutting width of the deck is, but many times you need to know what the actual width of the mower deck is. You’ll be disappointed if you buy a 48” mower deck and expect it to fit through a 48” gate.

The actual dimension of the width on a mower deck will be wider than the deck cutting width.

You must take into consideration the extra space of the mower deck shell on each end of the mower along with the space the discharge chute and anti-scalp rollers add to the deck width when calculating whether your lawn mower will fit through an opening, on your trailer, or in your storage area.

It is also important to select a mower deck size that will fit between elements in your yard such as trees and ornamental areas.

You will want to add in the width of the discharge chute being in the down position unless you want to continually get off your mower and raise the discharge chute to the mower between obstacles.

Measure the actual mower deck size using a tape measurer and extend the tape from the widest point on one side of the deck to the opposite side of the deck. Make sure you take into account the extra width added by anti-scalp rollers and discharge chute.

How Wide Are Riding Lawn Mowers?

The average riding lawn mower, also referred to as a garden tractor, is between 48 inches and 63 inches wide with the discharge chute in the upright position. Add 8 to 15 inches to the width when factoring the discharge chute in the downright position.

How Wide Are Zero Turn Mowers?

The average zero-turn mower is between 48 inches and 79inches wide with the discharge chute in the upright position. The most common zero turn mower deck cutting widths are 42″, 48″, 52″, 54″, 60″ and 72″.

When measuring your zero turn width, make sure you measure from and to the widest part of the deck. Using the discharge chute will up to an additional 15″ to the width.

While these are the most common mower deck sizes for zero turns. You can also find zero turns as narrow as a 36″ cutting width and as wide as a 96″ cutting width.

How Wide is a Standard Lawn Mower Deck?

Standard push mower or self-propelled mowers are 22 inches to 40 inches wide with a cutting deck width of 21 inches to 36 inches wide.

Most lawn mower manufacturers have standard mower deck sizes they offer. Here is a chart of some of the most common lawn mower brands and their average actual mower deck widths.

It is important you measure the actual width before you purchase your lawn mower if you need to stay within a certain deck size for transportation, storage, or yard obstacle reasons.

What Mower Deck Size Do You Need for Your Yard Size?

It is best to find the right-width mower for the amount of grass you need to mow. Here is a quick chart giving you an idea of the mower deck cutting width that best fits your yard size:

YARD SIZELAWN MOWER TYPEDECK SIZE
Less than 1 acrePush Mower, Self Propelled
Walk Behind
18″ – 36″ Deck Width
1 to 3 acresRiding Mower, Zero Turn36″ – 42″ Deck Width
3 to 4 acresRiding Mower, Zero Turn42″ – 54″ Deck Width
4 acres and moreZero Turn Mower60″ – 72″ Deck Width

In addition to selecting a lawn mower that fits your yard size, you need to also look at other lawn mower features including engine horsepower, type of mower decks, and other lawn mower functions that will make your mowing experience better.

For more details about this, read “Choose the Best Lawn Mower for Your Yard Size” and “Choosing Between a Residential and Commercial Zero Turn Mower“.

Do Smaller Mower Decks Cut Better?

Smaller mower decks do not cut better, however, the final cut appearance may look better using a smaller mower deck over a larger mower deck. There are several reasons that may affect the final cut’s overall look:

  • Tire Tracks
    You don’t really notice the tracks on a small lawn mower, but will see imprints from the tires on heavier mowers.
  • Number of Blades
    A small lawn mower will show a more even cut because there is only one blade and not multiple mower blades. The engine horsepower will only give you around 3600 RPMs on the engine. A single-blade mower is bolted directly to the engine so it does have quite a bit of blade speed to it.

    A bigger deck has two or even three blades that can cut unevenly if the deck is not set up correctly. If one of the blades is bent it will show a rigid cut in the lawn.

  • Follows Contours & Undulations
    A smaller format mower deck will follow the contours of the ground when there are small dips and undulations A larger deck will not always catch those.

    When the deck is 20″ or smaller in size it has an easier time getting the small rolls in the yard. You are able to cut the grass the first time instead of having to double-cut.

  • Able to Cut Shorter & Have a Carpet Look
    Most small lawn mowers have a 3″ to 4″ deep deck. With its smaller blade, it can produce a better vacuum off the blade than a larger format deck.

    The homeowner will be able to cut the grass shorter with a smaller deck without the chance of scalping the grass. The grass will appear better when cut short giving it a carpet-like look.

Can You Put a Bigger Deck on Your Mower?

There are very few manufacturers that make decks interchangeable with the lawn tractor you are mowing with.

With so many changes that will need to be made when trying to change mower decks sizes, why would you want to try? The amount of time and the expense to make the change will not be worth it.

Keep in mind, if you do choose to modify and change your lawn mower deck, you will run into trying to get the correct parts for your lawn mower.

If you need a bigger deck, I recommend buying a new lawn mower to save yourself the headache. If you really want to change out decks, check with your lawn mower dealer first to see if the deck you’re interested in will fit your lawn mower. You will also want to make sure it is cost-effective.

Don’t make the purchase before you talk to knowledgeable dealership personnel. An experienced dealer should be able to give you compatibility options along with the parts you may need to purchase to make the mower deck work for your lawn mower.

These parts may include new belts, pulleys, lift brackets, caster wheels, and lift parts.

Are Front Mount Deck Mowers Good?

Front mount mowers are good because their maneuverability is far better than belly mount mowers. The front mount mower will follow contours and trims under trees and split rail fences better than utilizing a belly mower.

Advantages of Front Mount Mower Decks

  • Maneuverability
  • Better contouring
  • Easier to service the deck and sharpen blades
  • Can mow in a wet spot without getting the tractor tires into the wet spot
  • Best to place the mower near a bank of water so the tractor doesn’t need to be close to the water.
  • When climbing a hill, you can lift the deck ever so slightly to transfer weight onto the tractor. This will allow the tractor to climb better without spinning a tire.

The disadvantage of Front Mount Mower Decks

  • Harder to change the height of cut

Stamped Decks Vs Fabricated Decks

There are two different styles of lawn mower decks: stamped decks and fabricated decks.  If you are heavily using your mower, you will definitely want to make sure you have a fabricated mower deck.

Most homeowners using their mowers for an hour or two per week will be fine using a stamped deck.

  • Stamped Deck – Mowers with stamped decks are typically less expensive. Stamped decks are literally stamped out of one sheet of steel. One advantage of the stamped deck is that it has good airflow for a good cut. A disadvantage is the thickness of the steel used.

    Because the deck is made out of one sheet, the steel is lighter gauge steel than the steel used in a fabricated deck. This can result in your deck shell being easily damaged when encountering a hard object.

  • Fabricated deck, also known as a welded deck, is made from thicker gauge steel and welded together. This allows the lawn mower deck to be more rigid than a stamped deck. They are able to take a little more abuse. The depth of deck available with a fabricated deck also increases your quality of cut.

Blade Tip Speed, Deck Depth, and Mower Blades Affect Quality of Cut

Blade tip speed, deck depth, and lawn mower blades all play a significant role in the quality of cut in a mower. A fabricated deck will provide you with a better cut over a stamped deck because the depth of the deck is typically deeper giving you a better lift of the grass.

The depth coupled with high lift blades spinning at a speed of about 18,500 fpm (feet per minute) is what is necessary to create the best cutting results. High lift blades along with the suction created by the depth of the deck lifts the grass tall.

The mower blade then passes by to precisely cut the grass. More information on the different types of lawn mower blades on the market today can be found in “This is the Way the Blade Goes on a Lawn Mower“.