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Straight-Line Depreciation Calculator
Straight-line depreciation spreads the cost of an asset evenly over its useful life. Each year’s expense is the same: the depreciable base, cost minus salvage value, divided by the number of years of use. It is the simplest method, the most widely used in financial statements, and the default under most accounting standards unless another pattern better reflects how the asset is used up.
Formula
Where
- Cost
- purchase price plus costs to get the asset ready for use
- Salvage value
- expected value at the end of its useful life
- Useful life
- number of years the asset will be used
Calculator
Result and step-by-step solution
20% of the depreciable base (9,000.00) each year for 5 years.
- Depreciable base10,000.00 − 1,000.00 = 9,000.00
- Spread evenly over the life9,000.005 = 1,800.00 per year
- Schedule
Year Book value at start Depreciation Accumulated Book value at end 1 10,000.00 1,800.00 1,800.00 8,200.00 2 8,200.00 1,800.00 3,600.00 6,400.00 3 6,400.00 1,800.00 5,400.00 4,600.00 4 4,600.00 1,800.00 7,200.00 2,800.00 5 2,800.00 1,800.00 9,000.00 1,000.00
How to use the formula
Cost includes the purchase price and everything needed to get the asset ready for use, such as delivery and installation. Salvage (or residual) value is what you expect to sell it for at the end of its life. The schedule shows the book value at the start of each year, the year’s depreciation, the accumulated total and the book value at the end, which reaches the salvage value after the final year.
A machine costing 10,000 with a salvage value of 1,000 and a 5-year life is depreciated by 1,800 a year, 18% of its cost. Tax rules often allow faster write-offs; compare the pattern with double declining balance or sum-of-the-years’-digits. The result matches Excel’s SLN(cost, salvage, life).
Frequently asked questions
- What is the straight-line depreciation formula?
- Annual depreciation = (cost − salvage value) ÷ useful life in years.
- What is the straight-line depreciation rate?
- 1 ÷ useful life of the depreciable base, so 20% a year for a 5-year asset.
- What if the asset is bought partway through the year?
- Most businesses prorate the first year by months of use, taking the remainder in an extra final year.
- Can salvage value be zero?
- Yes. Then the whole cost is depreciated over the useful life.
Last reviewed: September 26, 2026. Calculations run in your browser and were checked against numpy-financial, SciPy and published spreadsheet examples.