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2015.08.25
Two cars related tables released today: Tire codes - speed ratings and Tire codes - load index
2015.07.30
2015.04.06
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The table of tire load index codes. And also explanation of meaning of tire markings (bit by bit) with simple infographic.
Some facts
We explained below, how to read tire markings. The things you can read from symbol on a tire are:
• Nominal section width - this is a width of tire in milimeteres.
• Aspect ratio - this is a relation beetwen tire's high and width in percentages. Less ratio means wider tire. Historically, the most common was the profile 100% (equal width and height), but there are many different ratios popular nowadays like 80, 70, 60, 55 or 50 etc.
• Tire construction - this parameter says what is internal construction of the tire. Most common symbols are:
• R - for radial construction. It's the most popular type for cars.
• D - for diagonal construction. This type of tires is popular for example in agricultural machinery.
• B - for bias belt construction. This is special hybrid beetwen radial and diagonal construction. We can found this type of tires for example in the motorbikes.
• Diameter - for example 17'' diameter means that given tire fits a 17" diameter wheel.
• Load index - this parameter determines the maximum allowed load, which can be handled by single tire safely. It's a two or three digit symbol denoting maximum load in pounds or kilograms. For example load index 97 is related to maximum load of 730 kg (1,610 lb) per single tire. The table showing how to find maximum load in lb/kg (when we know load index) can be found in the calculator: Tire codes - load index.
• Speed rating - this parameter determines the maximum speed, which can be applied to the tire safely with load given by load index. In most common case it's a single letter symbol. For example single letter Q means, that maximum allowed speed is 100 mph (160km/h). The table showing how to find maximum speed (when we know the tire speed rating) can be found in the calculator: Tire codes - speed ratings.
Example
There is example symbol, which we can found on the car tire below. We can read from it, that:
• The tire has 225 mm of width.
• Its aspect ratio (height divided by width) is 55%. So, it's rather "wide" tire.
• The tire has radial construction.
• The tire fits a 17" diameter wheel.
• The load index of this tire is 97. It means, that its maximum load is 1,610 lb (730 kg). The table showing how to convert load index value into load in kilograms or pounds can be found in the calculator: Tire codes - load index.
• Its speed rating is W, which means that we can drive with maximum speed 168 mph (270 km/h). The table showing how to convert speed rating symbol into speed in mph or km/h can be found in the calculator: Tire codes - speed ratings.

#### Setup table:Load index code - digit load index symbol printed on your tireMaximum load (weight) [kg] - maximum allowed load in kilogramsMaximum load (weight) [lbs] - maximum allowed load in in pounds (UK, USA)Show all / Clear all

 Load index code Maximum load (weight) [kg] Maximum load (weight) [lbs] 33 115 254 34 117 260 35 121 267 36 125 276 37 128 282 38 132 291 39 136 300 40 140 309 41 145 320 42 150 331 43 155 342 44 160 353 45 165 364 46 170 375 47 175 386 48 180 397 49 185 408 50 190 419 51 195 430 52 200 441 53 206 454 54 212 467 55 218 481 56 224 494
 Load index code Maximum load (weight) [kg] Maximum load (weight) [lbs] 57 230 507 58 236 520 59 243 536 60 250 550 61 257 567 62 265 584 63 272 600 64 280 620 65 290 640 66 300 660 67 307 677 68 315 694 69 325 717 70 335 739 71 345 761 72 355 783 73 365 805 74 375 827 75 387 853 76 400 880 77 412 908 78 425 937 79 437 963 80 450 990
 Load index code Maximum load (weight) [kg] Maximum load (weight) [lbs] 81 462 1,019 82 475 1,047 83 487 1,074 84 500 1,100 85 515 1,135 86 530 1,170 87 545 1,202 88 560 1,230 89 580 1,280 90 600 1,300 91 615 1,356 92 630 1,390 93 650 1,430 94 670 1,480 95 690 1,520 96 710 1,570 97 730 1,610 98 750 1,650 99 775 1,709 100 800 1,800 101 825 1,819 102 850 1,870 103 875 1,929 104 900 2,000
 Load index code Maximum load (weight) [kg] Maximum load (weight) [lbs] 105 925 2,039 106 950 2,090 107 975 2,150 108 1,000 2,200 109 1,030 2,270 110 1,060 2,340 111 1,090 2,400 112 1,120 2,470 113 1,150 2,540 114 1,180 2,600 115 1,215 2,679 116 1,250 2,760 117 1,285 2,833 118 1,320 2,910 119 1,360 3,000 120 1,400 3,100 121 1,450 3,200 122 1,500 3,300 123 1,550 3,420 124 1,600 3,500 125 1,650 3,640