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Finance · Accounting

Depreciation Calculator

Spread an asset’s cost evenly across its useful life and see a full year-by-year book-value schedule.

Purchase price of the asset.
Estimated resale value at end of life.
How long the asset is used.
Try an asset
Annual depreciation
$3,600.00

Total depreciable amount: $18,000.00 written off evenly over 5 years.

Book value over time
Book value declining from cost to salvage value over the asset’s life$20,000.00$2,000.00Year 0Year 5

Book value falls in equal steps each year, from the $20,000.00 cost down to the $2,000.00 salvage value.

YearDepreciationAccumulatedBook value
1$3,600.00$3,600.00$16,400.00
2$3,600.00$7,200.00$12,800.00
3$3,600.00$10,800.00$9,200.00
4$3,600.00$14,400.00$5,600.00
5$3,600.00$18,000.00$2,000.00

Straight-line depreciation spreads an asset’s cost evenly over its useful life: annual depreciation = (cost − salvage value) ÷ useful life. A $20,000 machine with a $2,000 salvage value and a 5-year life depreciates $3,600 each year — its $18,000 depreciable cost divided by 5 — until its book value reaches the $2,000 salvage.

What straight-line depreciation is

Depreciation spreads the cost of a long-lived asset — a vehicle, machine, or piece of equipment — across the years it’s actually used, instead of expensing it all at once. The straight-line method is the simplest: it writes off the same amount every year. You take what the asset cost, subtract what you expect it to be worth at the end (its salvage value), and divide that depreciable amount by the number of years you’ll use it. The result is a steady annual expense and a book value that falls in equal steps.

annual = (cost − salvage) ÷ useful life

Cost is the purchase price, salvage the estimated end-of-life value, and useful life the number of years; book value after year t = cost − t × annual depreciation

Worked example

A machine costs $20,000, has an estimated $2,000 salvage value, and a 5-year useful life.

  1. 1
    Find the depreciable amount. Subtract salvage from cost: $20,000 − $2,000 = $18,000.
  2. 2
    Divide by the useful life. $18,000 ÷ 5 years = $3,600 of depreciation per year.
  3. 3
    Record the same expense every year. Each of the 5 years shows a $3,600 depreciation expense — that’s what “straight-line” means.
  4. 4
    Track accumulated depreciation. It builds up $3,600 at a time: $3,600, $7,200, $10,800, $14,400, then $18,000.
  5. 5
    Subtract from cost to get book value. Book value falls $20,000 → $16,400 → $12,800 → $9,200 → $5,600 → $2,000, ending exactly at the salvage value.

Depreciation schedule — $20,000 asset, $2,000 salvage, 5-year life

Straight-line depreciation of $3,600 per year. Accumulated depreciation grows to $18,000 and book value lands on the $2,000 salvage value.

YearDepreciationAccumulatedBook value
1$3,600$3,600$16,400
2$3,600$7,200$12,800
3$3,600$10,800$9,200
4$3,600$14,400$5,600
5$3,600$18,000$2,000

Reading the results

Straight-line vs. declining-balance. Straight-line charges the same expense every year, which suits assets that wear out evenly. Accelerated methods like declining-balance front-load the expense — larger deductions early on, smaller ones later — to match assets that lose most of their value quickly, such as computers or vehicles. Both methods write off the same total depreciable amount; they only differ in timing.

Salvage value matters. The salvage (or residual) value is your estimate of what the asset will fetch at the end of its useful life. A higher salvage value means a smaller depreciable amount and therefore a lower annual expense. Setting salvage to $0 means the whole cost is depreciated down to nothing over the life of the asset.

What is salvage value?
Salvage value (also called residual or scrap value) is your estimate of what an asset will be worth at the end of its useful life. You subtract it from the cost before depreciating, so the asset is only written down to its salvage value, not to zero.
What is the difference between straight-line and declining-balance depreciation?
Straight-line charges an equal expense every year, so book value falls in a straight line. Declining-balance is an accelerated method that takes larger deductions early and smaller ones later. Both write off the same total, but declining-balance shifts more expense into the first years.
How do I calculate the annual depreciation?
Subtract the salvage value from the cost to get the depreciable amount, then divide by the useful life in years. For a $20,000 asset with a $2,000 salvage over 5 years: ($20,000 − $2,000) ÷ 5 = $3,600 per year.
What is book value?
Book value is the asset’s remaining value on the balance sheet: cost minus accumulated depreciation. Under straight-line it drops by the same amount each year and, in the final year, equals the salvage value.
What if the salvage value is zero?
Then the depreciable amount equals the full cost, and the asset is written all the way down to $0 over its useful life. Annual depreciation is simply cost ÷ useful life.
Does straight-line depreciation ever go below salvage value?
No. The method stops depreciating once book value reaches the salvage value — that’s the floor. Total depreciation over the life equals cost minus salvage, never more.