Tyre Basics
How to read your tyre size (185/65 R15 88H explained)
Quick answer
Your tyre size is printed on the sidewall as a code like 185/65 R15 88H: width 185 mm, sidewall 65% of the width, radial, 15-inch rim, load index 88 and speed rating H.
Table of contents (5 sections)
- What each part of the tyre size means
- Load index and speed rating
- Where else to find your tyre size
- Other markings worth knowing
- DOT date code
- Tubeless or tube-type
- Can I change my tyre size?
- Frequently asked questions
- Is 185/65 R15 the same as 185/60 R15?
- Can I fit a wider tyre on the same rim?
- Do all four tyres need to be the same size?
The size code on your tyre sidewall tells you everything you need to buy the correct replacement. Take 185/65 R15 88H as an example — it is one of the most common sizes on Indian hatchbacks and compact sedans.
What each part of the tyre size means
| Code | Meaning | In this example |
|---|---|---|
| 185 | Tyre width in millimetres | 185 mm wide |
| 65 | Aspect ratio (sidewall height as % of width) | Sidewall is 65% of 185 mm ≈ 120 mm |
| R | Construction | Radial |
| 15 | Rim diameter in inches | Fits a 15-inch wheel |
| 88 | Load index | Up to 560 kg per tyre |
| H | Speed rating | Up to 210 km/h |
Load index and speed rating
Never fit a tyre with a lower load index or speed rating than your vehicle manufacturer recommends. A higher rating is fine; a lower one can be unsafe when the car is fully loaded.
Where else to find your tyre size
- On a sticker inside the driver's door or the fuel flap
- In the owner's manual
- On your last tyre invoice
Other markings worth knowing
DOT date code
A four-digit code such as 2324 means the tyre was made in week 23 of 2024. Tyres older than five to six years should be replaced even if tread remains.
Tubeless or tube-type
Most modern car tyres are marked TUBELESS. Two-wheeler and three-wheeler tyres can be either.
Can I change my tyre size?
Small changes within the manufacturer's approved list are fine. Keep the overall diameter within about 3% of the original so the speedometer and ABS stay accurate. If in doubt, send us a photo of the sidewall on WhatsApp.
Frequently asked questions
Is 185/65 R15 the same as 185/60 R15?
No. The 60 has a shorter sidewall, so the overall tyre is smaller. Only fit it if your car maker lists it as an approved size.
Can I fit a wider tyre on the same rim?
Often one size wider is possible on the same rim, but it depends on the rim width and wheel arch clearance. We check both before recommending it.
Do all four tyres need to be the same size?
Yes, unless your car was built with different front and rear sizes. Mixing sizes on the same axle affects braking and stability.
