Is the SILCA tire pressure calculator accurate?

Yes. This calculator implements SILCA's research-backed methodology used by professional cyclists and teams. Results are based on extensive testing and account for rider weight, tire specifications, surface conditions, and riding speed. The calculations match SILCA's published methodology.

Does the SILCA calculator minimize rolling resistance?

Yes — that's literally what it calculates. SILCA's algorithm finds the 'impedance breakpoint': the highest pressure you can run before road-surface impedance starts increasing your rolling resistance faster than lower casing losses save you. The PSI this calculator returns is the pressure at that breakpoint.

What PSI should I run on a 47mm gravel tire at 65kg?

For a 65kg total system weight on a 47mm measured high-performance tubeless gravel tire, the calculator gives: on hardpack (Category 1 Gravel), 33 PSI rear / 31.5 PSI front on a 650B wheel and 31.5 PSI rear / 30 PSI front on 700C. On moderate mixed gravel (Category 2 Gravel), about 3 PSI lower: 30 PSI rear / 28.5 PSI front on 650B, or 28.5 PSI rear / 27 PSI front on 700C.

What PSI should I run on a 61mm (2.4") MTB tire at 80kg?

For an 80kg total system weight on a 61mm (2.4") measured high-performance tubeless MTB tire on rough singletrack (Category 3 Gravel, 29er, Fast Single Track pace), the calculator gives 14.5 PSI rear / 13.5 PSI front (1.0/0.9 BAR).

Why does the calculator recommend pressure that seems too high or too low?

SILCA methodology accounts for modern tubeless tires and wider rims, which can run lower pressures safely. Results may differ from old pressure charts because they're personalized to YOUR exact setup - not generic recommendations. Lower pressure with tubeless tires provides better traction and comfort without pinch flat risk.

Does this work for tubeless tires?

Yes! Select a tubeless casing tier in the Tire Type dropdown for tubeless-specific recommendations. Going tubeless removes inner-tube pinch-flat risk at a given pressure, which is why most riders comfortably run lower than they would on an equivalent tubed setup in practice — but that's a separate thing from what actually moves this calculator's number, which is casing quality (high-performance tubeless computes higher than a stiffer, more puncture-resistant casing, tube or no tube).

Can I use this for MTB tire pressure?

Yes. The calculator accepts tire widths from 20-65mm and includes an MTB weight distribution: select "46.5/53.5 (Mountain Bikes)" in the Weight Distribution dropdown, plus your measured tire width. At 70-80kg total system weight on 57-65mm high-performance tubeless tires, it returns 9.5–23 PSI across Category 1-4 trail roughness.

How does this compare to SRAM's or other tire pressure calculators?

This calculator specifically implements SILCA's methodology with detailed surface condition options (10 levels from velodrome track to rough gravel) and pinch flat risk assessment. Different calculators use different methodologies - SILCA's approach focuses on balancing rolling resistance, comfort, and safety based on their research data.

Is there a SILCA tire pressure calculator app?

SilPSI works as a Progressive Web App (PWA), meaning you can install it directly from your browser to your phone's home screen — no app store needed. On iOS, tap the Share button and select "Add to Home Screen." On Android, tap the menu and select "Install App." It works offline after the first load and behaves just like a native app.

What tire pressure should I use for gravel riding?

Gravel tire pressure depends heavily on tire width and terrain. For a 40mm high-performance tubeless gravel tire at 75kg total system weight on 700C wheels, the calculator returns 29.5–42 PSI (2.0–2.9 BAR) from Category 1 Gravel down to Category 4 Gravel. Select a rougher surface condition for loose gravel and a smoother one for packed gravel roads.

How does average speed affect tire pressure?

SILCA's methodology applies a small linear speed adjustment: the faster your average pace, the slightly higher the starting pressure. The calculator's options run from Recreational (14 mph, about 23 km/h) to Pro Tour (24 mph, about 39 km/h). For a 75kg total system weight on 28mm high-performance tubeless tires on new pavement, that moves the result from 80.5 PSI rear / 78.5 PSI front to 82.5 PSI rear / 80.5 PSI front.

What about road bike tires with 28mm width?

28mm road tires are the modern standard for road cycling. For a typical 75kg total system weight on 28mm high-performance tubeless tires, the calculator gives 81.5 PSI rear / 79.5 PSI front (5.6/5.5 BAR) on new pavement, and 77 PSI rear / 75 PSI front on worn pavement. Measure your actual inflated tire width rather than using the labeled size, as actual width often differs by 1-3mm depending on rim width.

Can I use this calculator for Zipp wheels?

Yes! The calculator works with any wheel brand including Zipp, ENVE, Roval, DT Swiss, and others. The key measurement is your actual tire width when mounted and inflated on your specific wheelset.

What is a SILCA tire pressure chart?

A SILCA tire pressure chart shows recommended pressures for different rider weights and tire widths. Our Quick Reference Guide section provides general pressure ranges, but the calculator gives far more accurate results because it factors in YOUR specific setup.

Does this work with Maxxis or Pirelli tires?

Yes, the SILCA tire pressure calculator works with any tire brand including Maxxis, Pirelli, Continental, Schwalbe, Vittoria, and others. It uses your measured tire width and casing tier (the Tire Type dropdown: "High performance tire tubeless/latex tube", "Mid Range casing tubeless/latex tube", "Mid-Range casing butyl tube", "Puncture resistant tire tubeless/latex tube") to compute pressure, so the methodology applies regardless of brand. For Maxxis MTB tires, select "46.5/53.5 (Mountain Bikes)" weight distribution and your measured tire width.

Is the SILCA tire pressure calculator not working?

If the calculator isn't responding, try these steps: (1) Ensure all required fields are filled in, (2) Check that your weight value is within valid range, (3) Try refreshing the page, (4) Clear your browser cache. The calculator runs entirely in your browser with no server dependency.

What units does the calculator support?

The calculator supports dual unit systems: PSI (pounds per square inch) and BAR for pressure, and lbs (pounds) and kg (kilograms) for weight. Results are displayed in both PSI and BAR simultaneously.

How is front and rear tire pressure different?

Front and rear pressures differ because weight isn't split evenly between the wheels. The calculator's Weight Distribution options are 48/52 front/rear for road bikes, 47/53 for gravel, 46.5/53.5 for mountain bikes and 50/50 for triathlon/TT/track. The rear carries more weight, so it gets the higher number: a 75kg total system weight on 28mm tubeless tires on new pavement gives 81.5 PSI rear / 79.5 PSI front on the road split, versus 80.5 PSI on both wheels at 50/50.

SILCA Tire Pressure Calculator

Calculate your optimal bike tire pressure using SILCA's research-backed methodology. Free online calculator for road bikes, gravel bikes, MTB, and cyclocross — supporting tubeless, latex-tube and butyl-tube clincher tires. Get a personalized starting PSI and BAR based on your total system weight, tire width, surface conditions, and riding speed. No email or signup needed.

Calculated Baselines Across Bike Disciplines

Calculator output for common setups using high-performance tubeless casings. Weights are total system weight (rider + bike + gear).

Discipline & Setup	Front PSI / BAR	Rear PSI / BAR
Road · 75 kg, 28mm, 700C, new pavement	79.5 PSI (5.5 BAR)	81.5 PSI (5.6 BAR)
Gravel · 65 kg, 47mm, 700C, Cat 1 hardpack	30 PSI (2.1 BAR)	31.5 PSI (2.2 BAR)
Gravel · 65 kg, 47mm, 700C, Cat 2 mixed gravel	27 PSI (1.9 BAR)	28.5 PSI (2 BAR)
MTB · 80 kg, 61mm (2.4"), 29er, Cat 3 rough trail	13.5 PSI (0.9 BAR)	14.5 PSI (1 BAR)

Get Your Tire Pressure

Accurate tire pressure for road, gravel, and MTB bikes. Tubeless and clincher support.

Enter Total System Weight

(Rider + Bike + Gear)

lbs

kg

Surface Condition

Surface Guide Learn More

Measured Tire Width

Measuring Guide

Wheel Diameter

Tire Type

How does this change my tire pressure?

Average Speed

Weight Distribution

More SilPSI Tire Pressure Calculators

Riding something else today? Get numbers built around your bike and your terrain.

Only ride pavement?Road Bike Tire Pressure Calculator (25–32mm)Spending more time off-road?Gravel Tire Pressure Calculator by Weight (38–50mm)Mostly on the trail?MTB Tire Pressure Calculator (29er & 27.5 Trail)Running tubeless on everything?Tubeless Tire Pressure Calculator (All Casing Tiers)

SILCA Tire Pressure Quick Reference

Every range below is this calculator's own output across a spread of typical setups. For a starting point based on YOUR weight, tire specs and surface, use the calculator above.

Tire Pressure by Bike Type

Bike Type	Tire Setup	Calculator Range
Road Bike Tire Pressure Calculator	Tubeless or butyl-tube clincher · 25–32mm · 700C · new/worn pavement	56.5–98 PSI (3.9–6.8 BAR)
Gravel Bike Tire Pressure Calculator	High-performance tubeless · 38–50mm · 700C/650B · Cat 1–4 gravel	20–49 PSI (1.4–3.4 BAR)
Mountain Bike Tire Pressure Calculator	High-performance tubeless · 57–65mm (2.2–2.6") · 29er/27.5" · Cat 1–4 trail	9.5–23 PSI (0.7–1.6 BAR)
Tubeless Tire Pressure Calculator	All 3 tubeless casing tiers · road 28mm · 700C · new pavement	71.5–82 PSI (4.9–5.7 BAR)

Road Bike Pressure by Tire Width (High-Performance Tubeless, New/Worn Pavement)

Tire Width	Calculator Range
23mm	101.5–111.5 PSI (7.0–7.7 BAR)
25mm	89–98 PSI (6.1–6.8 BAR)
28mm	74.5–82 PSI (5.1–5.7 BAR)
32mm	60–66.5 PSI (4.1–4.6 BAR)

MTB Pressure by Tire Width (High-Performance Tubeless, 29er, Cat 2–3 Trail)

Tire Width	Calculator Range
2.1" (53mm)	19–23.5 PSI (1.3–1.6 BAR)
2.2" (57mm)	16–20 PSI (1.1–1.4 BAR)
2.4" (61mm)	13.5–16.5 PSI (0.9–1.1 BAR)
2.5" (64mm)	11–14 PSI (0.8–0.9 BAR)

How these ranges were calculated: each range is the lowest and highest front or rear pressure the calculator returns for 70–80kg (154–176lbs) total system weight (rider + bike + gear) across the setups listed, at a moderate group ride pace (fast singletrack pace for MTB). Your own number depends on your exact weight, measured tire width, casing and surface, so use the calculator above for your personalized starting point.

How to Use the Calculator

1Enter Your Total System Weight

Add up your body weight, bike weight, and any gear you'll be carrying (bottles, bags, tools, etc.). You can enter the weight in either pounds (lbs) or kilograms (kg).

2Select Surface Condition

Choose the type of terrain you'll be riding on, from smooth indoor tracks to rough gravel roads. Use the Surface Guide link for help identifying your riding conditions.

3Measure Your Tire Width

Use a caliper or ruler to measure the actual width of your inflated tire (not the labeled size). Check the Measuring Guide link for detailed instructions on getting an accurate measurement.

4Choose Wheel Diameter & Tire Type

Select your wheel size (700C, 650B, etc.) and your tire's casing tier, from high-performance tubeless/latex tube down to puncture-resistant. A more supple casing gets a higher starting pressure.

5Set Average Speed & Weight Distribution

Enter your typical riding speed and select your bike type (road, TT/Triathlon, gravel, or mountain). The calculator uses this to optimize pressure for your riding style.

6Calculate & Use Your Results

Click the Calculate button to get your optimized front and rear tire pressures in both PSI and BAR.

Copy Results: Save your pressures to clipboard for reference
Share: Share your results with friends or your cycling group
Calculate New: Reset the form to calculate pressures for a different setup

⚠️Important Tips

•Always check that calculated pressures are within your tire and rim manufacturer's recommended ranges
•Start conservative (slightly higher) and adjust based on feel and performance
•Pay attention to pinch flat risk warnings and follow the recommendations
•Use a quality pressure gauge for accurate inflation

Frequently Asked Questions

Have more questions? Visit our contact page to get in touch.