Inputs
Contract effective date.
Usually today.
Added to total allowance.
Optional grace miles before fees apply.
Example data
| Scenario | Start | Term | Annual | Start Odo | Current Odo | As‑of | Fee/mi |
|---|---|---|---|---|---|---|---|
| Commuter | 2024‑01‑15 | 36 | 12,000 | 250 | 15,875 | 2025‑10‑06 | $0.25 |
| Road‑trip heavy | 2024‑07‑01 | 24 | 10,000 | 120 | 18,900 | 2025‑10‑06 | $0.30 |
| Weekend driver | 2025‑01‑01 | 36 | 7,500 | 50 | 4,200 | 2025‑10‑06 | $0.20 |
Click “Load example” to populate the form with the first row.
Results
Units: miles
pace (mi/day)
| Month # | Date | Allowed cumulative | Projected cumulative | Variance (proj − allow) |
|---|
Formulas used
- Total allowed miles:
allowedAnnual × (termMonths ÷ 12) + extraMiles - Total days in term: exact days between startDate and startDate + termMonths
- Days elapsed: exact days between startDate and asOfDate (clamped to [0, totalDays])
- Allowed to date:
totalAllowed × (daysElapsed ÷ totalDays) - Actual miles:
currentOdo − startOdo - Daily pace:
actualMiles ÷ max(1, daysElapsed) - Projected miles at end:
dailyPace × totalDays - Projected variance at end:
projectedMiles − totalAllowed - Billable overage:
max(0, projectedVariance − tolerance) - Estimated fee:
billableOverage × feePerMile
How to use this calculator
- Enter your lease start date, the current date, term (months), and allowed miles per year.
- Enter your start and current odometer readings. Include any extra miles purchased and the overage fee per mile.
- Click Calculate to see pacing KPIs, the monthly schedule, and the cumulative comparison chart.
- Use Export CSV to download the monthly schedule. Use Export PDF to save a summary with the schedule and chart image.
- Adjust inputs to compare scenarios and keep an eye on projected variance and potential fees.
FAQs
The projection assumes your current daily pace continues unchanged to the end of the term. If your driving pattern changes, recalculate with updated odometer and date.
We prorate the total allowance by time:
totalAllowed × (daysElapsed ÷ totalDays), using exact calendar days in your specific term.Your annual allowance scaled by the term plus any miles you purchased upfront:
allowedAnnual × (termMonths ÷ 12) + extraMiles.Yes—add them to Extra miles purchased. If miles are redeemable only at end‑of‑term, include them here since the projection compares against end‑state allowance.
Most contracts imply a uniform pacing of miles. We model allowance as linear over time to make it easy to compare with your actual pace.
We compute billable overage after optional tolerance and multiply by your fee per mile. Taxes or other lease‑end charges are not included.
Yes—change the current date while keeping odometer fixed to simulate fewer days of driving, or re‑calculate later with a smaller odometer increase to see new projections.
Enter your start odometer as recorded at delivery (including demo miles). The calculator uses differences, so any starting value is fine.
No. This tool focuses on miles and variance. Always follow your maintenance schedule and lease terms to avoid additional charges.
A negative variance means you’re under the allowance to date—good news. The projection will show whether you stay under based on current pace.
Yes—use the camera icon on the chart toolbar to download as PNG. The PDF export also embeds the chart image automatically.
For now, the calculator displays miles. You can still convert: 1 mile ≈ 1.60934 km. A future version may add unit switching.