Understanding tyre sizes is essential for every vehicle owner. Tyres are the only contact point between your vehicle and the road, and selecting the correct tyre size ensures safety, performance, comfort, and fuel efficiency. However, many drivers overlook one critical factor hidden in tyre markings — how much weight a tyre can safely carry.

At Tyre Vortex, we help drivers understand not only tyre dimensions but also tyre strength and load capacity. This guide explains tyre sizes in detail and shows how to identify a tyre’s weight-bearing capability.

Attentive mechanic preparing a check list at repair garage

What Is a Tyre Size?

A tyre size is a standardized code printed on the tyre sidewall. It provides information about the tyre’s width, height, construction, rim size, load capacity, and speed rating.

Example:
205/55 R16 91V

Each part of this code has a specific purpose.

How to Read a Tyre Size (Step-by-Step)

1. Tyre Width (205)

This number shows the width of the tyre in millimetres.

• Wider tyres = better grip
• Narrower tyres = better fuel efficiency

205 means the tyre is 205 mm wide.

2. Aspect Ratio (55)

This is the height of the tyre’s sidewall as a percentage of the width.

• Lower ratio = sportier handling
• Higher ratio = more comfort

55 means the sidewall height is 55% of 205 mm.

3. Construction Type (R)

• R = Radial construction (most modern tyres)

Radial tyres provide better durability, grip, and efficiency.

4. Rim Diameter (16)

This number indicates the wheel size in inches.

16 means the tyre fits a 16-inch rim.

Load Index Explained: How Much Weight Can a Tyre Carry?

The load index is one of the most important but misunderstood parts of a tyre size. It tells you how much weight a single tyre can safely support when inflated correctly.

Example:
205/55 R16 91V

Here, 91 is the load index.

What Does Load Index Mean?

The load index is a numerical code that corresponds to a specific weight capacity.

🔹 Important:
The load index value applies per tyre, not the total vehicle weight.

Common Tyre Load Index & Weight Capacity Chart

Example:
If your tyre has a load index of 91, it can safely carry 615 kg per tyre.

Why Load Index Is Critical

Using tyres with an incorrect load index can cause:

• ❌ Tyre overheating
• ❌ Premature tyre failure
• ❌ Reduced braking performance
• ❌ Increased risk of blowouts

At Tyre Vortex, we always recommend choosing tyres with a load index equal to or higher than manufacturer specifications.

Speed Rating (V)

The final letter indicates the maximum speed the tyre can safely handle.

Common ratings:

• T = up to 190 km/h
• H = up to 210 km/h
• V = up to 240 km/h

Load index and speed rating must both be correct for safe driving.

Why Understanding Tyre Weight Capacity Matters

Your tyres support:

• Vehicle weight
• Passengers
• Cargo
• Fuel load

If tyres cannot handle this weight safely, performance and safety are compromised. Correct tyre load capacity ensures:

• ✔ Safe handling
• ✔ Stable braking
• ✔ Longer tyre life
• ✔ Better fuel efficiency

Where to Find the Correct Tyre Load Rating

You can find the recommended tyre load index in:

• Owner’s manual
• Driver-side door sticker
• Manufacturer specifications
• Your existing tyre sidewall

If unsure, Tyre Vortex experts can guide you accurately.

Can You Use a Higher Load Index Tyre?

Yes.
Using a tyre with a higher load index than required is generally safe.

However:

• Using a lower load index is unsafe and not recommended.

Common Tyre Load Mistakes to Avoid

• Ignoring load index numbers
• Overloading vehicles
• Choosing cheaper tyres with lower load ratings
• Mixing load indexes on the same axle

Avoiding these mistakes ensures safer driving.

FAQs – Tyre Load & Size Explained