Calculator Inputs
Example Data Table
| Example | Purchase Price | Current Value | Age | Annual Mileage | Forecast Years | Projected End Value |
|---|---|---|---|---|---|---|
| Compact Sedan | $24,500 | $17,800 | 3 years | 10,000 mi | 4 | $10,942 |
| Family SUV | $38,000 | $28,400 | 2 years | 13,500 mi | 5 | $16,981 |
| Luxury Crossover | $56,000 | $41,250 | 2 years | 9,000 mi | 6 | $23,614 |
Formula Used
1) Mileage penalty
Mileage Penalty = max(0, (Annual Mileage − Mileage Benchmark) ÷ 1,000) × Penalty Rate
2) Adjusted annual depreciation rate
Adjusted Rate = max(1, (Base Depreciation × Age Taper × Condition Factor × Brand Factor × Market Factor) + Mileage Penalty)
3) Next year projected value
Next Value = max(Salvage Floor, Current Value − Depreciation Amount + Reconditioning Recovery)
4) Reconditioning recovery
Reconditioning Recovery = smaller of 3% of current value or 35% of annual reconditioning spend
This model forecasts a balanced scenario and also creates optimistic and conservative scenario bands for visual planning.
How To Use This Calculator
- Enter the vehicle’s original purchase price.
- Add the current market value if you already know it.
- Set vehicle age and current mileage.
- Choose how many years to forecast.
- Enter depreciation rates for first year and normal later years.
- Adjust mileage assumptions, condition, brand retention, and market trend.
- Set a salvage floor and any yearly reconditioning budget.
- Click Calculate Forecast to view the summary cards, chart, yearly table, and export options.
FAQs
1) Is this calculator an official appraisal tool?
No. It is a planning calculator. It helps estimate future resale value using adjustable assumptions, but actual offers depend on market demand, service history, accidents, trim, and local buyer interest.
2) Should I enter current market value or leave it blank?
Enter current market value when you already have a reliable estimate. Leave it blank when you want the calculator to estimate a starting value from purchase price, age, and depreciation assumptions.
3) Why does mileage change depreciation so much?
Higher mileage usually lowers resale value because it suggests more wear, shorter remaining life, and greater maintenance risk. The calculator adds a penalty only when mileage exceeds your benchmark.
4) What does the brand retention index mean?
It is a relative resale strength setting. A value above 100 means the brand tends to hold value better than average, while a value below 100 means weaker value retention.
5) Can maintenance spending fully cancel depreciation?
Usually not. Maintenance protects value and reduces buyer discounts, but most upkeep spending is only partly recovered at resale. That is why the calculator uses a limited recovery amount.
6) Why is there a salvage floor setting?
It prevents unrealistic forecasts. Older vehicles still keep some residual value for parts, basic transport, or trade-in. The floor stops the model from dropping below that practical minimum.
7) What is the difference between balanced, optimistic, and conservative?
Balanced is the main forecast. Optimistic assumes slightly slower value loss. Conservative assumes faster loss. Comparing all three helps you plan resale timing and ownership cost risk.
8) How often should I update the forecast?
Update it whenever mileage, condition, maintenance records, or used-car market conditions change. Rechecking every few months gives better resale timing and a more useful ownership plan.