The Straight Line Depreciation Calculator spreads an asset's depreciable cost evenly across every year of its useful life, producing the same expense figure in year one as in the final year. Enter the asset's cost, its expected salvage value and its useful life in years, and the calculator returns the annual depreciation expense and a full year-by-year schedule down to the salvage value.
Straight-line is the simplest and most widely used depreciation method precisely because of this evenness. There is no acceleration, no formula involving the shrinking book value, and no complex fraction to track from year to year, just one fixed dollar amount repeated for as many years as the asset is expected to remain useful.
*These results are estimates for information only, not tax or accounting advice.*
Understand the straight-line formula
Straight-line depreciation expenses the difference between an asset's cost and its expected salvage value evenly across its useful life. The formula is Annual Depreciation = (Cost - Salvage Value) / Useful Life, and that single result repeats identically every year until the asset's book value reaches the salvage figure.
Take an asset costing $10,000 with an expected salvage value of $1,000 and a useful life of 5 years. The depreciable base is $10,000 minus $1,000, or $9,000, and dividing that base by 5 years gives an annual depreciation expense of $1,800.00. The Straight Line Depreciation Calculator repeats that exact $1,800.00 figure for each of the five years, so the book value falls in equal steps: $8,200.00 after year one, $6,400.00 after year two, $4,600.00 after year three, $2,800.00 after year four, and exactly $1,000.00, the salvage value, after year five.
See why this method is the accounting default
Because the expense is identical every year, straight-line depreciation produces predictable, easy-to-forecast numbers on a financial statement, which is a major part of its appeal for internal reporting even when a business uses a different, accelerated method for tax purposes.
It also matches assets whose usefulness genuinely declines at a roughly constant rate year after year, such as office furniture or a building, rather than assets that lose most of their value quickly and then hold it, which accelerated methods are better suited to model.
The Straight Line Depreciation Calculator's schedule makes this constancy visible immediately: every row in the expense column shows the same number, while the accumulated depreciation column climbs in perfectly even steps and the book value column falls in the same even steps until it lands exactly on the salvage value in the final year.
Compare straight-line against accelerated methods
Accelerated methods, such as double-declining balance or sum-of-the-years-digits, front-load depreciation expense into the early years of an asset's life and taper off toward the end. On the identical $10,000 cost, $1,000 salvage, 5-year asset used above, double-declining balance would expense $4,000.00 in year one alone, more than double the straight-line figure, while sum-of-the-years-digits would expense $3,000.00 in year one.
Both accelerated methods eventually converge to the same total $9,000.00 depreciated over the full 5 years that straight-line reaches, they simply distribute that total differently across the years.
Choosing straight-line over an accelerated method changes when the expense hits the books, not how much total expense an asset generates over its life, since both approaches always depreciate the same total depreciable base by the time the asset reaches full salvage value.
Know how salvage value and useful life affect the result
Raising the estimated salvage value lowers the depreciable base and therefore lowers the annual straight-line expense, since less of the asset's cost needs to be recovered through depreciation.
Extending the useful life spreads the same depreciable base across more years, which also lowers the annual expense, while shortening the useful life concentrates the same total depreciation into fewer, larger annual amounts.
Both salvage value and useful life are estimates rather than guaranteed figures, and accounting standards or tax rules may specify particular useful life conventions for certain asset classes. The Straight Line Depreciation Calculator applies whatever figures are entered directly, so the accuracy of the result depends on the accuracy of those two estimates.
Know the limits of this calculation
This calculation assumes an asset is placed in service at the very start of a full year and depreciates for complete annual periods with no partial-year conventions, no bonus depreciation, and no Section 179 expensing applied.
Real-world tax depreciation often involves mid-year, mid-quarter or other partial-year conventions specified by tax law, and financial statement depreciation may follow policies set by a company's accounting standards rather than the simple annual model shown here.
Use the Straight Line Depreciation Calculator to understand the underlying even-expense mechanic and to build a quick planning estimate. For actual tax filings or audited financial statements, confirm the specific convention and method required against current tax rules or accounting standards.
Frequently asked questions
What is the formula for straight-line depreciation?
The formula for straight-line depreciation is (Cost - Salvage Value) / Useful Life. This produces one fixed annual expense that repeats identically every year of the asset's useful life until the book value reaches the salvage value.
How much does a $10,000 asset with $1,000 salvage depreciate each year over 5 years?
A $10,000 asset with a $1,000 salvage value depreciated over a 5-year useful life expenses $1,800.00 every year under the straight-line method, since the $9,000 depreciable base divided by 5 years equals $1,800.00.
Why is straight-line the most common depreciation method?
Straight-line is the most common depreciation method because it is simple to calculate, produces predictable annual figures for financial reporting, and reasonably matches assets whose usefulness declines at a fairly constant rate over time.
Does straight-line depreciate more or less total expense than accelerated methods?
Straight-line depreciates the exact same total expense over an asset's full useful life as accelerated methods; the two approaches simply distribute that same total differently, with accelerated methods expensing more in the early years and less later.
What happens if I raise the salvage value estimate?
Raising the salvage value estimate lowers the depreciable base, which lowers the annual straight-line expense, since less of the asset's original cost needs to be recovered as depreciation over its useful life.
Summary
The Straight Line Depreciation Calculator divides an asset's depreciable base, cost minus salvage value, evenly across its useful life using Annual Depreciation = (Cost - Salvage Value) / Useful Life. A $10,000 asset with a $1,000 salvage value over a 5-year life expenses exactly $1,800.00 every year, reaching the $1,000 salvage value precisely at the end of year five.
This is the simplest and most predictable depreciation method, though accelerated alternatives may better match assets that lose usefulness faster early on. Figures shown are estimates, not tax or accounting advice.