Depreciation Calculator - Asset Book Value

Depreciation spreads an asset’s depreciable cost across the periods that benefit from its use. The depreciation calculator supports straight-line and double-declining-balance methods and reports depreciation for a selected year, accumulated depreciation to date, and remaining book value. Accountants, controllers, and operators use it to sketch expense and book-value paths before committing to a capitalization policy or a replacement decision. Straight-line depreciation is (cost − salvage) ÷ useful life, so each year receives the same expense. Double-declining balance applies twice the straight-line rate to beginning book value, then floors the charge so book value does not fall below salvage. In this implementation, the declining-balance charge is also compared with remaining straight-line depreciation and cannot exceed book value minus salvage. For a $10,000 asset, $1,000 salvage, and five-year life, straight-line expense is $1,800 every year. Double-declining expense is $4,000 in year 1, then $2,400, then $1,440 in year 3 as the book value declines. Use straight-line when wear is expected to be even, such as furniture or a building component. Use double-declining balance when an asset delivers more service in early years, such as vehicles or technology, and you want expense recognized sooner. Selecting a year shows that year’s expense and the accumulated total, which is useful for a mid-life sale analysis or an impairment discussion. This is a planning estimate, not a tax engine. U.S. tax depreciation often uses MACRS, half-year or mid-quarter conventions, listed-property limits, and bonus depreciation. Useful life here is an accounting estimate, not an IRS recovery period. Salvage should be the expected residual you will not depreciate. If the result will support financial statements, tax filings, or a sale negotiation, reconcile the method and life to the applicable accounting or tax rules. Book value after the selected year is the usual starting point for a gain or loss on sale: selling price minus book value. Straight-line keeps expense stable for budgeting; double-declining front-loads expense and leaves a lower book value earlier, which can matter if you dispose of the asset in year 2 or 3. Change only the method on the same cost, salvage, and life to isolate timing. Do not treat these annual amounts as cash outflows; depreciation is an allocation of a cost you already paid or financed.