# Accumulated Depreciation Calculator

URL: https://speedycalculator.com/calculators/finance/accumulated-depreciation/
Last updated: 2026-10-25

> The accumulated depreciation calculator works out how much of an asset's cost has been depreciated after a number of years and its net book value, using straight-line, double-declining balance, sum-of-the-years' digits or units-of-production depreciation.

## Inputs

- Method
- Cost of the asset
- Salvage value
- Useful life (years)
- Years elapsed (years)
- Total expected units
- Units produced so far

## Results

- Accumulated depreciation
- Net book value
- Share of cost depreciated
- Straight-line depreciation per year

## Formula

```
Straight-line: (cost − salvage) × years ÷ life
Double-declining: book value = cost × (1 − 2 ÷ life)^years (not below salvage)
Sum-of-years' digits: (cost − salvage) × [Σ of (life − k + 1) for k = 1..years] ÷ [life(life + 1)/2]
Units of production: (cost − salvage) × units produced ÷ total units
```

## Explanation

Accumulated depreciation is the total depreciation recorded since an asset was bought. It sits on the balance sheet as a contra-asset, reducing the asset's cost to its net book value. Accelerated methods front-load the expense.

### How to use the Accumulated Depreciation Calculator

- **Method**
- **Cost of the asset**
- **Salvage value**
- **Useful life**
- **Years elapsed**
- **Total expected units**
- **Units produced so far**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Choose the method and enter the asset cost, salvage value, useful life and years elapsed (or units produced for the units method).

### Tips

- Use figures for the same period (a month, a quarter or a year) for every input so ratios compare like with like.
- Track the metric over time – the trend usually tells you more than a single value.
- Compare your result with industry benchmarks, which vary a lot between sectors.
- Treat the result as a starting point for a decision, then check the assumptions behind each input.

### Common mistakes to avoid

- Mixing monthly and yearly numbers in the same calculation.
- Using revenue where the formula needs profit (or the other way round).
- Forgetting hidden costs such as taxes, fees, overheads or your own time.

### Inputs explained

FieldWhat to enterMethodChoose one: Straight-line, Double-declining balance, Sum-of-the-years' digits, Units of productionCost of the assetAmount in your currencySalvage valueAmount in your currencyUseful lifeIn yearsYears elapsedIn yearsTotal expected unitsA numberUnits produced so farA number

### What each result means

- **Net book value** = [Cost of the asset] - [Accumulated depreciation]
- **Share of cost depreciated** = [Accumulated depreciation]÷[Cost of the asset]×100
- **Straight-line depreciation per year** = ([Cost of the asset] - [Salvage value])÷[Useful life]

### Example values

How the main result changes when **Cost of the asset** changes and everything else stays at the example values above:

Cost of the assetAccumulated depreciation25,0008,00037,50013,00050,00018,00062,50023,00075,00028,000100,00038,000

## Worked example

Inputs — Method: Straight-line; Cost of the asset: $50,000; Salvage value: $5,000; Useful life: 10 years; Years elapsed: 4 years; Total expected units: 100,000; Units produced so far: 38,000.

Results — **Accumulated depreciation = $18,000.00**; Net book value = $32,000.00; Share of cost depreciated = 36 %; Straight-line depreciation per year = $4,500.00.

## FAQ

**What is accumulated depreciation?**
The total depreciation charged on an asset since it was put into use.

**Is accumulated depreciation an asset or a liability?**
Neither – it is a contra-asset account that reduces the asset's value.

**Which method should I use?**
Straight-line suits assets used evenly; accelerated methods suit assets that lose value fast.

**What formula does the Accumulated Depreciation Calculator use?**
Straight-line: (cost − salvage) × years ÷ life.


## Sources

- [IRS Publication 946 – How to depreciate property](https://www.irs.gov/publications/p946)