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02Tires

Tire Pressure Calculator

Optimal pressure for any tire, rim, rider, and surface.

Front73 lb25 mm21 mm rimRear110 lb25 mm21 mm rim
0140
57psiFront
0140
86psiRear

All methods

MethodFrontRearNotes
Berto62 psi4.3 bar93 psi6.4 barTraditional 15% drop guideline (Berto, 1988).
Impedance57 psi3.9 bar86 psi5.9 barLower for rough surfaces (impedance research).
Heine47 psi3.2 bar70 psi4.8 barWide-tire philosophy, lower across the board.
ENVETubeless onlyTubeless only — ENVE charts assume a tubeless setup.
Silca85 psi5.9 bar88 psi6.0 barReverse-engineered Silca Pro formula.

A starting point. Adjust by feel.

How this works

Tire pressure science is contested. Different published models optimize for different goals (lowest rolling resistance vs. comfort vs. flat resistance) and assume different casing qualities. This tool ships five methods side by side and lets you pick a primary. Each method is an honest implementation of publicly published research or data, or — in the case of Silca — a reverse-engineered formula attributed as such.

Berto
Frank Berto's 1988 "15% tire drop" guideline (Bicycling magazine; codified by Sheldon Brown). Higher, traditional pressures. Doesn't differentiate by surface or tubeless setup.
Impedance
Berto baseline scaled by a surface roughness factor and a tubeless allowance. Incorporates the impedance principle described by Josh Poertner (Silca) and validated by Bicycle Rolling Resistance: optimal pressure is lower on rough surfaces.
Heine
Berto baseline scaled by Jan Heine's published recommendations from Bicycle Quarterly. The "wide tire, lower pressure" philosophy — 25–45% below Berto, assuming a supple casing.
ENVE
Direct lookup against ENVE's 2026 tire-pressure charts (Road / Gravel / Mountain). ENVE publishes the full tables, so we encode them verbatim. Tubeless only.
Silca
Reverse-engineered formula for Silca's Pro Tire Pressure Calculator. Includes Silca's pinch-flat energy balance (surfaced as a note on the row when at risk) and the 70 psi hookless caution. Valid for riders 34–205 kg.

Hookless rims are capped at 72.5 psi / 5 bar per ETRTO and manufacturer specs. Any calculated value above the cap is clamped and flagged in the table; a warning surfaces if the cap fires.

View full methodology on GitHub →

Sources: Frank Berto / Bicycling 1988, Sheldon Brown, Silca blog (Poertner), Bicycle Rolling Resistance, Jan Heine / Bicycle Quarterly, Rene Herse Cycles, ETRTO standards, Zipp and ENVE hookless documentation.