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Load Index and Speed Rating Decoder and Chart

The number and letter after the tire size tell you how much weight each tire can carry and its maximum rated speed. Enter the code to decode it.

By Sidewall Math editorial teamUpdated Facts last checked
What changed
  • : First published.
On this page
  1. Where to find the code
  2. Load index chart (70–126)
  3. Speed rating chart
  4. Choosing replacement tires
  5. Light truck tires

Load index and speed rating decoder

Where to find the code

On the sidewall, the service description follows the size: in P225/65R17 102H, the load index is 102 and the speed symbol is H. NHTSA's tire safety brochure shows the same layout, and the vehicle's Tire and Loading Information label lists the original size.

Load index chart (70–126)

Maximum load per tire, from tire maker tables. Pounds are converted at 2.20462 lb per kg and rounded.

Index kg lb Index kg lb Index kg lb
70 335 739 89 580 1,279 108 1,000 2,205
71 345 761 90 600 1,323 109 1,030 2,271
72 355 783 91 615 1,356 110 1,060 2,337
73 365 805 92 630 1,389 111 1,090 2,403
74 375 827 93 650 1,433 112 1,120 2,469
75 387 853 94 670 1,477 113 1,150 2,535
76 400 882 95 690 1,521 114 1,180 2,601
77 412 908 96 710 1,565 115 1,215 2,679
78 425 937 97 730 1,609 116 1,250 2,756
79 437 963 98 750 1,653 117 1,285 2,833
80 450 992 99 775 1,709 118 1,320 2,910
81 462 1,019 100 800 1,764 119 1,360 2,998
82 475 1,047 101 825 1,819 120 1,400 3,086
83 487 1,074 102 850 1,874 121 1,450 3,197
84 500 1,102 103 875 1,929 122 1,500 3,307
85 515 1,135 104 900 1,984 123 1,550 3,417
86 530 1,168 105 925 2,039 124 1,600 3,527
87 545 1,202 106 950 2,094 125 1,650 3,638
88 560 1,235 107 975 2,150 126 1,700 3,748

Speed rating chart

Symbol km/h mph
L 120 75
M 130 81
N 140 87
P 150 93
Q 160 99
R 170 106
S 180 112
T 190 118
U 200 124
H 210 130
V 240 149
W 270 168
Y 300 186

Note that H sits between U and V, out of alphabetical order. A "Z" inside the size (for example 245/40ZR18) is an older marking for tires rated above 240 km/h; the service description after the size gives the specific rating.

Choosing replacement tires

Continental's plus-sizing bulletin sets out the rule tire makers apply: load capacity and speed rating equal to or greater than the original equipment tire. Find the originals on the door placard or in the owner's manual. The bulletin also warns never to inflate below the vehicle maker's recommended pressure, and that extra load (XL) tires may need different pressures to carry the same load.

The ratings are tested maximums for a tire in good condition at the correct pressure. They are not a recommended driving speed, and an underinflated, damaged or overloaded tire cannot be relied on to meet them.

Light truck tires

LT tires often carry a dual load index such as 121/118, plus a load range letter (C, D, E and so on) that indicates the tire's construction and maximum pressure. Load and inflation tables for LT tires differ from passenger tables, so use the tire maker's LT data when comparing.

Common questions

What does 91V mean on a tire?

91 is the load index: 615 kg (1,356 lb) per tire. V is the speed rating: 240 km/h (149 mph).

Can I use a higher load index than original?

Yes. Tire maker guidance is equal to or greater than the original. Do not go lower. Keep the vehicle maker's recommended pressure; Continental notes you should never inflate below it even with a higher load index tire.

Can I use a lower speed rating?

Continental's bulletin says the speed rating must be equal to or greater than the original equipment fitment. Some winter tire practices differ by country; follow the vehicle and tire maker's guidance.

Why do light truck tires have two load numbers?

Codes like 121/118 give the load for a tire used singly (121) and for each tire when mounted in pairs on a dual-wheel axle (118).

Sources

  1. Bridgestone, Speed and load rating charts explained
  2. Continental Tire, PSIB 06-03 Tire Plus Sizing of Passenger and Light Truck Vehicles
  3. NHTSA, Tire Safety: Everything Rides On It

Checked Nov 11, 2026. Spot an error? Tell us.

Related

GuideHow to read a tire sidewallSize, load, speed, DOT date code and UTQG grades decoded.GuidePlus sizing rulesThe four checks before changing tire or wheel size.CalculatorTire size comparisonDiameter, width, speedometer and 3% check for two sizes.
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