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235/45R18 Tire Size
All You Need to Know About 235/45R18 Tires
235/45R18 tires have a section width of 235 millimeters (mm), an aspect ratio of 45%, radial construction, and an 18-inch wheel diameter. Before buying tires sized 235/45R18, converting 235/45R18 size in inches, comparing it with similar tire sizes like 245/45R18, and researching the best 235/45R18 tires helps drivers shop for the right set for their vehicles.
What Are The Dimensions of 235/45R18 Tires in Inches?
235/45R18 tires have a section width of ≈ 9.25 inches, an aspect ratio of ≈ 4.16 inches, and a wheel diameter of 18 inches. The overall tire diameter is ≈ 26.33 inches, the circumference is ≈ 82.71 inches, and the recommended rim width range is 7.5 to 9.0 inches.
235/45R18 tire size in millimeters and inches are presented in the below table:
235/45R18 Tire Size Dimensions | 235/45R18 Tire Size Dimensions in Inches (") | Formula to Convert 235/45R18 Size in Inches (") |
235 mm (section width) | ≈ 9.25" | 235 ÷ 25.4 = 9.25 |
106 mm (sidewall height) | ≈ 4.16" | (235 × 0.45) ÷ 25.4 = 4.16 |
18 (rim diameter) | 18" | Given |
669 mm (overall diameter) | ≈ 26.33" | (2 × 106 ÷ 25.4) + 18 = 26.33 |
2102 mm (circumference) | ≈ 82.71" | 26.33 × 3.1416 = 82.71 |
335 mm (radius) | ≈ 13.16" | 26.33 ÷ 2 = 13.16 |
In inches, the 235/45R18 tire size can be represented as 26.3" × 9.3" R18.
Are 235/45R18 low-profile tires?
Yes, 235/45R18 is a low-profile tire because it has an aspect ratio of 45, meaning a sidewall height of ≈ 4.16" (106 mm), which falls below the general threshold of 50 or less aspect ratio for the low-profile standard.
Most Recommended 235/45R18 Tires
Drivers opting for 235/45R18 tires usually want a responsive yet composed setup that works smoothly across everyday driving scenarios without locking them into a single use case. Top 5 Tire Recommendations for 235/45R18 (by conditions) include:
Comparison of 235/45R18 With Similar Tire Sizes
Compare 235/45R18 with other tire sizes, such as 245/45R18 and 235/40R19, to learn the key differences between them and make the right choice when buying new tires.
What Is The Difference Between 235/45R18 vs 245/45R18?
The main difference between 235/45R18 and 245/45R18 is the tread width. The 235/45R18 tire is 0.39'' (10mm) narrower than the 245/45R18 tire, resulting in a ≈0.17'' (4 mm) shorter sidewall height and ≈0.40'' (9 mm) shorter overall diameter.
The tire dimensions or measurement difference between 235/45R18 vs 245/45R18 is shown in the table below.
Tire dimensions | 235/45R18 tires dimensions in millimeters (mm) and inches (") | 245/45R18 tires dimensions in millimeters (mm) and inches (") | Difference b/w 235/45R18 and 245/45R18 in millimeters (mm) and inches (") | Percentage ≈ difference b/w 235/45R18 and 245/45R18 |
Section Width | 235 mm (≈ 9.25") | 245 mm (≈ 9.65") | 10 mm (≈ 0.39") | ≈ 4.3% |
Sidewall Height | 106 mm (≈ 4.16") | 110 mm (≈ 4.33") | 4 mm (≈ 0.17") | ≈ 3.8% |
Overall Diameter | 669 mm (≈ 26.33") | 678 mm (≈ 26.73") | 9 mm (≈ 0.40") | ≈ 1.3% |
Circumference | 2102 mm (≈ 82.71") | 2131 mm (≈ 83.92") | 29 mm (≈ 1.14") | ≈ 1.4% |
Radius | 335 mm (≈ 13.16") | 339 mm (≈ 13.36") | 4 mm (≈ 0.17") | ≈ 1.2% |
Rim Diameter | 457.2 mm (18.00") | 457.2 mm (18.00") | - | - |
Rim width range | 7.5’’- 9.0’’ | 7.5’’- 9.0’’ | - | - |
Can I use 245/45R18 instead of 235/45R18?
Yes, using a 245/45R18 tire size instead of a 235/45R18 is generally accepted, as the 10mm difference in tread width only brings minor changes to clearance, handling, and comfort. Major clearance issues are unlikely with 245/45R18 instead of 235/45R18, as there is only a 1.3% diameter difference, which should not affect fender and suspension; but you still need to make sure compatibility.
Handling and grip might become insignificantly better due to the wider contact patch of the 245/45R18 size; however, some extra noise can be expected, though not remarkable. Comfort can become slightly better as the 0.35 ‘’ (9mm) larger diameter of the 245/45R18 size contributes to better shock absorption. Also, expect a 1.3% speedometer difference when switching from 235/45R18 to 245/45R18 tire size.
What Is The Difference Between 235/45R18 vs 235/40R19?
The key differences between 235/45R18 and 235/40R19 are that the 235/45R18 has a 12 mm (0.47") taller sidewall, ≈ 2 mm (0.09") shorter overall diameter, ≈ 6 mm (0.24") shorter circumference, and ≈ 1 mm (0.05") shorter radius compared to the 235/40R19 size.
The tire dimensions or measurement difference between 235/45R18 vs 235/40R19 is shown in the below table:
Tire dimensions | 235/45R18 tires dimensions in millimeters (mm) and inches (") | 235/40R19 tires dimensions in millimeters (mm) and inches (") | Difference b/w 235/45R18 and 235/40R19 in millimeters (mm) and inches (") | Percentage ≈ difference b/w 235/45R18 and 235/40R19 |
Section Width | 235 mm (≈ 9.25") | 235 mm (≈ 9.25") | - | - |
Sidewall Height | 106 mm (≈ 4.16") | 94 mm (≈ 3.70") | ≈12 mm (≈ 0.46") | ≈ 11.1% |
Overall Diameter | 669 mm (≈ 26.33") | 671 mm (≈ 26.40") | ≈2 mm (≈ 0.09") | ≈ 0.3% |
Circumference | 2101 mm (≈ 82.71") | 2107 mm (≈ 82.94") | ≈6 mm (≈ 0.24") | ≈ 0.3% |
Radius | 334 mm (≈ 13.16") | 335 mm (≈ 13.20") | ≈1 mm (≈ 0.05") | ≈ 0.3% |
Rim Diameter | 457.2 mm (18.00") | 482.6 mm (19.00") | ≈25.4 mm (≈ 1.00") | ≈5.6% |
Rim width range | 7.5’’- 9.0’’ | 8.0’’- 9.5’’ | - | - |
Can I use 235/40R19 instead of 235/45R18?
No, you can’t use a 235/40R19 size instead of a 235/45R18 size without changing your wheels, due to the different wheel size (19’’ vs 18’’). The 235/40R19 tire simply won’t fit on an 18’’ wheel, so you will need to have an extra 19'' wheel set to use this tire size. If you decide to upgrade to a 19’’ wheel set, the 235/40R19 tires will feel more sporty due to their lower profile compared to the 235/45R18 size (40 vs 45). No significant speedometer errors will be generated as the overall diameter between the two sizes is nearly ≈ 0.1” apart.
All You Need to Know About 235/45R18 Tires
235/45R18 tires have a section width of 235 millimeters (mm), an aspect ratio of 45%, radial construction, and an 18-inch wheel diameter. Before buying tires sized 235/45R18, converting 235/45R18 size in inches, comparing it with similar tire sizes like 245/45R18, and researching the best 235/45R18 tires helps drivers shop for the right set for their vehicles.
What Are The Dimensions of 235/45R18 Tires in Inches?
235/45R18 tires have a section width of ≈ 9.25 inches, an aspect ratio of ≈ 4.16 inches, and a wheel diameter of 18 inches. The overall tire diameter is ≈ 26.33 inches, the circumference is ≈ 82.71 inches, and the recommended rim width range is 7.5 to 9.0 inches.
235/45R18 tire size in millimeters and inches are presented in the below table:
235/45R18 Tire Size Dimensions | 235/45R18 Tire Size Dimensions in Inches (") | Formula to Convert 235/45R18 Size in Inches (") |
235 mm (section width) | ≈ 9.25" | 235 ÷ 25.4 = 9.25 |
106 mm (sidewall height) | ≈ 4.16" | (235 × 0.45) ÷ 25.4 = 4.16 |
18 (rim diameter) | 18" | Given |
669 mm (overall diameter) | ≈ 26.33" | (2 × 106 ÷ 25.4) + 18 = 26.33 |
2102 mm (circumference) | ≈ 82.71" | 26.33 × 3.1416 = 82.71 |
335 mm (radius) | ≈ 13.16" | 26.33 ÷ 2 = 13.16 |
In inches, the 235/45R18 tire size can be represented as 26.3" × 9.3" R18.
Are 235/45R18 low-profile tires?
Yes, 235/45R18 is a low-profile tire because it has an aspect ratio of 45, meaning a sidewall height of ≈ 4.16" (106 mm), which falls below the general threshold of 50 or less aspect ratio for the low-profile standard.
Most Recommended 235/45R18 Tires
Drivers opting for 235/45R18 tires usually want a responsive yet composed setup that works smoothly across everyday driving scenarios without locking them into a single use case. Top 5 Tire Recommendations for 235/45R18 (by conditions) include:
Comparison of 235/45R18 With Similar Tire Sizes
Compare 235/45R18 with other tire sizes, such as 245/45R18 and 235/40R19, to learn the key differences between them and make the right choice when buying new tires.
What Is The Difference Between 235/45R18 vs 245/45R18?
The main difference between 235/45R18 and 245/45R18 is the tread width. The 235/45R18 tire is 0.39'' (10mm) narrower than the 245/45R18 tire, resulting in a ≈0.17'' (4 mm) shorter sidewall height and ≈0.40'' (9 mm) shorter overall diameter.
The tire dimensions or measurement difference between 235/45R18 vs 245/45R18 is shown in the table below.
Tire dimensions | 235/45R18 tires dimensions in millimeters (mm) and inches (") | 245/45R18 tires dimensions in millimeters (mm) and inches (") | Difference b/w 235/45R18 and 245/45R18 in millimeters (mm) and inches (") | Percentage ≈ difference b/w 235/45R18 and 245/45R18 |
Section Width | 235 mm (≈ 9.25") | 245 mm (≈ 9.65") | 10 mm (≈ 0.39") | ≈ 4.3% |
Sidewall Height | 106 mm (≈ 4.16") | 110 mm (≈ 4.33") | 4 mm (≈ 0.17") | ≈ 3.8% |
Overall Diameter | 669 mm (≈ 26.33") | 678 mm (≈ 26.73") | 9 mm (≈ 0.40") | ≈ 1.3% |
Circumference | 2102 mm (≈ 82.71") | 2131 mm (≈ 83.92") | 29 mm (≈ 1.14") | ≈ 1.4% |
Radius | 335 mm (≈ 13.16") | 339 mm (≈ 13.36") | 4 mm (≈ 0.17") | ≈ 1.2% |
Rim Diameter | 457.2 mm (18.00") | 457.2 mm (18.00") | - | - |
Rim width range | 7.5’’- 9.0’’ | 7.5’’- 9.0’’ | - | - |
Can I use 245/45R18 instead of 235/45R18?
Yes, using a 245/45R18 tire size instead of a 235/45R18 is generally accepted, as the 10mm difference in tread width only brings minor changes to clearance, handling, and comfort. Major clearance issues are unlikely with 245/45R18 instead of 235/45R18, as there is only a 1.3% diameter difference, which should not affect fender and suspension; but you still need to make sure compatibility.
Handling and grip might become insignificantly better due to the wider contact patch of the 245/45R18 size; however, some extra noise can be expected, though not remarkable. Comfort can become slightly better as the 0.35 ‘’ (9mm) larger diameter of the 245/45R18 size contributes to better shock absorption. Also, expect a 1.3% speedometer difference when switching from 235/45R18 to 245/45R18 tire size.
What Is The Difference Between 235/45R18 vs 235/40R19?
The key differences between 235/45R18 and 235/40R19 are that the 235/45R18 has a 12 mm (0.47") taller sidewall, ≈ 2 mm (0.09") shorter overall diameter, ≈ 6 mm (0.24") shorter circumference, and ≈ 1 mm (0.05") shorter radius compared to the 235/40R19 size.
The tire dimensions or measurement difference between 235/45R18 vs 235/40R19 is shown in the below table:
Tire dimensions | 235/45R18 tires dimensions in millimeters (mm) and inches (") | 235/40R19 tires dimensions in millimeters (mm) and inches (") | Difference b/w 235/45R18 and 235/40R19 in millimeters (mm) and inches (") | Percentage ≈ difference b/w 235/45R18 and 235/40R19 |
Section Width | 235 mm (≈ 9.25") | 235 mm (≈ 9.25") | - | - |
Sidewall Height | 106 mm (≈ 4.16") | 94 mm (≈ 3.70") | ≈12 mm (≈ 0.46") | ≈ 11.1% |
Overall Diameter | 669 mm (≈ 26.33") | 671 mm (≈ 26.40") | ≈2 mm (≈ 0.09") | ≈ 0.3% |
Circumference | 2101 mm (≈ 82.71") | 2107 mm (≈ 82.94") | ≈6 mm (≈ 0.24") | ≈ 0.3% |
Radius | 334 mm (≈ 13.16") | 335 mm (≈ 13.20") | ≈1 mm (≈ 0.05") | ≈ 0.3% |
Rim Diameter | 457.2 mm (18.00") | 482.6 mm (19.00") | ≈25.4 mm (≈ 1.00") | ≈5.6% |
Rim width range | 7.5’’- 9.0’’ | 8.0’’- 9.5’’ | - | - |
Can I use 235/40R19 instead of 235/45R18?
No, you can’t use a 235/40R19 size instead of a 235/45R18 size without changing your wheels, due to the different wheel size (19’’ vs 18’’). The 235/40R19 tire simply won’t fit on an 18’’ wheel, so you will need to have an extra 19'' wheel set to use this tire size. If you decide to upgrade to a 19’’ wheel set, the 235/40R19 tires will feel more sporty due to their lower profile compared to the 235/45R18 size (40 vs 45). No significant speedometer errors will be generated as the overall diameter between the two sizes is nearly ≈ 0.1” apart.
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