Tire Sizing Guide · 5-minute read
How to Find and Read Your Lawn Mower Tire Size
Learn what the numbers on your tire mean and which additional details to check before ordering a replacement tire or complete wheel assembly.
Finding the right replacement lawn mower tire starts with the numbers on its sidewall. Those numbers tell you the tire’s size—but they don’t tell you everything you need to know when replacing a complete tire-and-wheel assembly.
Here’s how to read your tire size, understand what each number means, and check the details that help you order the right replacement.
Start With the Tire’s Sidewall
Look along the side of your existing tire for a raised or molded size marking. You might see something like 15x6.00-6.
Dirt can make the lettering difficult to read. Wipe the sidewall with a damp cloth and check both sides if necessary. A flashlight held at an angle can help make the raised numbers easier to see.
Write down the complete size or take a clear photo. Keep the numbers, decimal points, and separators together rather than relying on memory.
Check the tire you plan to replace. Your mower’s front and rear tires may use different sizes.
What Does 15x6.00-6 Mean?
Many lawn mower tires use a three-number size format. For 15x6.00-6, the numbers describe three different dimensions.
Example tire size
15 × 6.00 − 6
Overall diameter · Section width · Rim diameter
| Number | What it means |
|---|---|
| 15 | Nominal overall tire diameter: approximately 15 inches |
| 6.00 | Nominal tire section width: approximately 6 inches |
| 6 | Rim diameter: the tire fits a 6-inch rim |
The first number describes the tire’s overall height across its center.
The second number describes its section width—the width across the sidewalls. It is not the rim width, and it may differ from the width of the tread that touches the ground.
The last number identifies the rim diameter at the bead seat, where the tire seats against the wheel. It does not describe the axle hole or the outside diameter of the metal rim’s lip.
Another example is 20x10.00-8: a tire with a nominal 20-inch overall diameter and 10-inch section width that fits an 8-inch rim.
Why Your Tape Measure May Show Something Different
Tire sizes are nominal dimensions. A tire marked “15” may not measure exactly 15 inches tall.
Actual dimensions can vary with the tire design, manufacturer, rim width, inflation, load, and wear. A flat tire can also look much shorter than its marked size suggests.
Some Tires Use a Different Size Format
Not every lawn and garden tire uses three numbers. You may find a marking such as 4.80-8. In that format, the first part identifies the nominal section width, and the last number identifies the rim diameter. The overall tire diameter is not stated directly.
Do not interpret 4.80-8 as an approximately 4.8-inch-tall tire.
If the marking looks unfamiliar, record it exactly and check the product specifications or ask for help before ordering. Different numbering formats should not be treated as interchangeable without confirming compatibility.
Matching the Tire Size Is Only the First Step
For a tire-only replacement, confirm that the replacement is compatible with your existing rim, including its diameter and approved width.
Also check:
- Tread pattern: Choose a tread appropriate for the equipment and its work.
- Load and speed ratings: The replacement must meet the equipment’s requirements.
- Tube requirements: Confirm whether the tire and wheel combination uses an inner tube.
- Available clearance: Check the space around the tire, especially near steering components, the mower deck, and the frame.
Matching the printed size does not automatically make every tire in that size suitable for your application.
Buying a Complete Wheel Assembly? Check the Center, Too
A complete assembly includes the tire mounted on a wheel. The tire size still matters, but the wheel must also match how your equipment mounts it.
Two assemblies can have the same tire size and completely different mounting details.
For a Wheel That Slides Onto an Axle
Confirm:
- Axle diameter and bearing or bushing inside diameter
- Hub length
- Hub position or offset
- Bearing or bushing type
- Any keyway, drive connection, or retaining hardware requirements
Hub length describes the length of the wheel’s center hub along the axle. Hub position determines how the wheel sits relative to that hub and the equipment.
A matching axle-hole size alone does not confirm that an assembly will fit.
For a Wheel That Bolts Onto a Hub
Confirm:
- Number of bolt holes
- Bolt pattern or bolt-circle diameter
- Center-bore diameter
- Wheel offset
- Required lug-hole and mounting-seat style
Do not use the distance between two convenient holes as a substitute for confirming the correct bolt pattern. The measurement method depends on the number and arrangement of the holes.
If you’re unsure which mounting style you have, take clear photos of the center of the wheel and how it attaches to the mower.
What If You Can’t Read the Tire Size?
Start with your equipment’s owner’s manual or parts information. The model number—and sometimes the serial number—can help identify the original tire or wheel assembly.
However, older equipment may have replacement wheels that differ from the original specifications. Compare the manual’s information with what is actually installed.
Measurements and photos can help narrow down a replacement, but a tape measure alone may not identify the exact tire size.
Useful information includes:
- Equipment make, model, and serial number
- Any readable tire markings
- Photos of the tire, wheel center, and mounting arrangement
- Approximate overall diameter and section width
- Wheel mounting measurements
- Original or replacement part number, if available
For rim diameter, avoid measuring across the outside edges of the rim and assuming that measurement is its listed size. Look for a wheel marking or confirm the bead-seat diameter through the specifications.
A Quick Check Before You Order
Before placing your order, make sure you can answer these questions:
- What is the complete tire size?
- Am I buying a tire, an inner tube, or a complete wheel assembly?
- Does the tire meet my equipment’s rim, load, speed, and tread requirements?
- If I’m buying an assembly, have I confirmed its mounting dimensions?
- Will the replacement have enough clearance?
Taking a few minutes to gather those details can help prevent an incorrect order and get your equipment back to work sooner.