Gravel Tire Pressure Calculator
Enter your weight, tire width and gravel surface for a personalized starting front and rear PSI and BAR — any tire brand, hardpack to chunky gravel.
Baseline Tire Pressure at 65 kg Total System Weight
40mm measured tire width · high-performance tubeless · moderate group ride pace
| Wheel · Surface | Front PSI / BAR | Rear PSI / BAR |
|---|---|---|
| 700C (29") · Cat 1 Gravel — hardpack / light gravel | 39.5 PSI (2.7 BAR) | 41.5 PSI (2.8 BAR) |
| 700C (29") · Cat 2 Gravel — moderate mixed gravel | 35.5 PSI (2.5 BAR) | 37.5 PSI (2.6 BAR) |
| 650B (27.5") · Cat 1 Gravel — hardpack / light gravel | 41.5 PSI (2.9 BAR) | 43.5 PSI (3 BAR) |
| 650B (27.5") · Cat 2 Gravel — moderate mixed gravel | 38 PSI (2.6 BAR) | 39.5 PSI (2.7 BAR) |
Get Your Gravel Tire Pressure
Enter your total system weight, measured tire width, gravel surface and casing type. The calculator applies the 47/53 gravel front/rear split automatically.
How to Use This Calculator
1Enter Your Total System Weight
Add up your body weight, bike weight and any gear you'll be carrying. Enter it in pounds (lbs) or kilograms (kg).
2Select Gravel Surface Category
Choose Category 1 through 4, from hardpack dirt or light gravel through deep, chunky or loose gravel.
3Measure Your Tire Width
28–55mm covers fast gravel/all-road tires through standard and plus-size gravel setups. Measure the tire's actual inflated width, not the sidewall size.
4Choose Wheel Diameter & Tire Type
Select 700C or 650B, then your casing: high-performance, mid-range or puncture-resistant tubeless, or a mid-range butyl-tube setup.
5Set Average Speed
Pick the pace closest to your typical ride. Weight distribution is fixed at 47/53 front/rear for gravel bikes, so there's nothing else to choose.
6Calculate & Use Your Results
Get a personalized starting front and rear PSI and BAR in one click, then copy or share the numbers.
How Gravel Tire Pressure Works
Gravel tires are wide enough (28–55mm) to run meaningfully lower pressure than a road bike, but the terrain varies far more than pavement does, from smooth hardpack to loose, chunky rock. The SILCA methodology behind this calculator balances rolling resistance against surface roughness to estimate the highest pressure that doesn't cost you speed to vibration losses — a starting point for testing, not a fixed answer.
Gravel tire pressure by width (65 kg total system weight, Category 2 gravel, 700C, high-performance tubeless)
| Tire Width | Front PSI | Rear PSI |
|---|---|---|
| 32mm | 51 | 53.5 |
| 38mm | 39 | 40.5 |
| 40mm | 35.5 | 37.5 |
| 45mm | 29.5 | 30.5 |
| 50mm | 24 | 25.5 |
Starting-point reference only — use the calculator above for your own weight and setup, then adjust based on feel.
Does casing type change gravel tire pressure?
It does, but not strictly along tubeless-vs-tubed lines. The Tire Type input is a casing-quality spectrum: high-performance tubeless casings are the most supple, so they compute the highest starting pressure. Puncture-resistant tubeless casings are stiffer and heavier for durability, so they compute a lower number, at 37.5 PSI rear versus 41.5 PSI rear for the same 65 kg / 40mm / Category 1 setup — even though both are tubeless. A mid-range butyl tube setup lands in between at 39 PSI rear. What going tubeless actually buys you is removing inner-tube snakebite risk at whatever pressure you run; it doesn't automatically mean a lower number from this calculator, and it doesn't remove the risk of casing damage, rim strikes, burping or loss of control if you run too little air.
Front vs. rear on gravel
Gravel bikes carry more weight over the rear wheel, roughly a 47/53 front/rear split, so the rear tire needs slightly more air for the same contact-patch shape as the front. This calculator applies that split automatically to every result; you never need to add or subtract PSI yourself.
Gravel pressure tips
- Going tubeless removes inner-tube pinch-flat risk at whatever pressure you choose to run, which is what lets most riders comfortably test lower than they would on a tubed setup.
- 40mm is the common middle ground: narrower gravel tires compute noticeably higher, wider ones noticeably lower, at the same weight.
- Match the surface you'll spend most of the ride on, not the smoothest or roughest section of it.
- Rim width shifts your measured tire width, which is why this calculator asks for that number directly instead of the size printed on the sidewall.
- Never exceed the lower of your tire's and rim's printed maximum pressure, and only run combinations your manufacturers list as compatible.
If you are running narrow slicks on paved tarmac, compute higher-pressure breakpoints with the road bike tire pressure calculator.
Riding chunky singletrack or rocky downhills on wide 50mm+ rubber? Switch to the MTB tire pressure calculator for trail and singletrack.
Worried about burping and rim strikes on rocky fire roads? Compare casing tiers on the tubeless tire pressure calculator.
Frequently Asked Questions
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