Tire Pressure Calculator
Tire Pressure is evaluated from Recommended PSI, Current Tire PSI and Your Car's MPG. The calculation reports PSI Difference, Estimated MPG Loss and Effective MPG.
Results
About the Tire Pressure Calculator
The calculator uses a multi formula configuration. Each reported value is read as a direct evaluation of the stored rules with the declared field formats and units.
Formula basis:
PSI difference = recommended - current (floor 0)
MPG loss% = PSI under x 0.2%/PSI
Effective MPG = baseline MPG x (1 - loss fraction)
Annual extra cost = (15,000 / actual MPG - 15,000 / baseline MPG) x gas price
Interpret the outputs in the order shown by the result fields. Optional inputs affect only the outputs that depend on those variables.
Formula & How It Works
The calculation applies the following relations exactly as recorded in the metadata: PSI difference = recommended - current (floor 0) MPG loss% = PSI under x 0.2%/PSI Effective MPG = baseline MPG x (1 - loss fraction) Annual extra cost = (15,000 / actual MPG - 15,000 / baseline MPG) x gas price Each output field is produced by substituting the supplied inputs into the relevant relation and then applying the declared rounding or text format.
Worked Examples
Example 1: Toyota Camry: recommended 35 PSI, currently 28 PSI, 32 MPG, $3.45/gal
Inputs
With Recommended PSI = 35, Current Tire PSI = 28, Your Car's MPG = 32 and Gas Price = 3.45 as the stated inputs, the result is PSI Difference = 7 PSI, Estimated MPG Loss = 1.4% and Effective MPG = 31.6 MPG. Each value corresponds to the declared output fields.
Example 2: Ford F-150: recommended 40 PSI, currently 33 PSI, 22 MPG, $3.55/gal
Inputs
With Recommended PSI = 40, Current Tire PSI = 33, Your Car's MPG = 22 and Gas Price = 3.55 as the stated inputs, the result is PSI Difference = 7 PSI, Estimated MPG Loss = 1.4% and Effective MPG = 21.7 MPG. Each value corresponds to the declared output fields.
Example 3: Honda CR-V: recommended 32 PSI, currently 38 PSI (overinflated), 30 MPG, $3.40
Inputs
With Recommended PSI = 32, Current Tire PSI = 38, Your Car's MPG = 30 and Gas Price = 3.4 as the stated inputs, the result is PSI Difference = 0 PSI, Estimated MPG Loss = 0% and Effective MPG = 30 MPG. Each value corresponds to the declared output fields.
Example 4: Honda Odyssey: recommended 36 PSI, currently 25 PSI (very low), 28 MPG, $3.50
Inputs
With Recommended PSI = 36, Current Tire PSI = 25, Your Car's MPG = 28 and Gas Price = 3.5 as the stated inputs, the result is PSI Difference = 11 PSI, Estimated MPG Loss = 2.2% and Effective MPG = 27.4 MPG. Each value corresponds to the declared output fields.
Common Use Cases
- Check if tire PSI is within safe and efficient range
- Estimate MPG loss from underinflated tires
- Understand when TPMS warning light should illuminate