What is Depreciation Calculator?
Depreciation spreads the cost of a tangible asset across the years it generates revenue, matching expense to use instead of hitting the income statement on day one. The method you choose decides the shape of that spread: straight-line is flat, declining balance and sum-of-years-digits front-load it, units of production follows physical wear, and MACRS follows the IRS rulebook.
The choice matters twice. On the books, accelerated methods push expense into early years — flattering later-year net income and smoothing perceived performance. On the tax return, front-loaded deductions defer cash taxes, and a deferred tax is an interest-free loan from the treasury. That is why most US businesses run two schedules at once: straight-line for the financial statements, MACRS for the return.
This calculator builds the complete schedule for any of the five standard methods, lets you compare them side by side, and prices the tax shield — the present value of every deduction dollar at your tax rate. Enter a sale price and it books the gain or loss on disposal as well.
When to Use This Calculator
- Before buying equipment — test the deduction pattern under each method.
- When preparing annual accounts — generate the schedule for every fixed asset.
- At tax planning time — switch to Tax shield mode and read the present value.
- When a buyer offers on used equipment — compare the price with book value.
- While building a financial model — pull first-year depreciation straight into the P&L.
- When a lender asks for the fixed-asset note — export the schedule as support.
Steps:
- Enter the asset basics — cost, salvage value and useful life come from the purchase record or your fixed-asset policy.
- Choose the method — straight-line for steady expense, declining balance or SYD for front-loading, units of production for wear-based assets, MACRS for the US tax return.
- Check the method-specific inputs — the declining-balance factor and switch, the MACRS property class, or total and annual units.
- Read the schedule — each row shows beginning book value, the deduction, the running accumulated total and where the asset lands at year end.
- Price the tax shield — switch to Tax shield mode, set your marginal rate and discount rate, and read the present value of the deductions.
- Model a disposal — enter a sale price and year to book the gain or loss against remaining book value before you commit to a sale.
Formula
Use Cases
- Building the fixed-asset schedule for a small business — one row per asset, straight-line for the books.
- Estimating this year's tax deduction for new equipment before you buy it.
- Comparing book vs tax depreciation to explain the deferred-tax balance to a lender.
- Deciding between a lease and a purchase — depreciation often drives the lease maths.
- Pricing a used-asset sale: book value versus offer price becomes the gain or loss.
- Forecasting cash taxes in a financial model with accelerated first-year write-offs.
Key Benefits
- Match expense to the years the asset actually produces revenue.
- Accelerated methods defer cash taxes — a timing benefit worth real money at today's discount rate.
- A precise book value underpins resale pricing, insurance cover and collateral valuations.
- Side-by-side comparison shows exactly how much timing differs between methods.
- Book and tax schedules in one place make the deferred-tax reconciliation obvious.
Pro Tips
- Run the compare mode before choosing — the totals tie; only the shape changes.
- Use straight-line for the books and MACRS for the return — the gap is your deferred tax, not an error.
- Set the discount rate to your WACC so the shield present value reflects real financing costs.
- Check the sensitivity grid: a longer life barely moves next year's deduction, salvage moves the whole schedule.
- Record the method and switch policy in the fixed-asset policy so audits reconcile without digging.
- For units-of-production assets, track mileage or hours monthly — the schedule is only as good as the usage count.
Common Mistakes to Avoid
- Depreciating below salvage value — book methods must stop at the floor; only MACRS goes to zero.
- Forgetting the final-year plug — declining balance never lands on salvage by itself; the last year is adjusted.
- Using useful life instead of the IRS property class for MACRS — cars and computers are 5-year property whatever you believe their life is.
- Treating the tax shield as free money — it is a timing benefit; its value is the discounted stream, not the nominal total.
- Ignoring salvage when comparing methods — MACRS writes off more simply because it ignores salvage, not because it is more generous overall.
Key Terms Explained
- Book value:
- Cost minus accumulated depreciation — what the asset is worth on the balance sheet, not its market price.
- Salvage value:
- The residual floor at the end of life; book methods stop depreciating here.
- MACRS:
- Modified Accelerated Cost Recovery System — the IRS depreciation system for US tax returns, built on property classes and table rates.
- Half-year convention:
- The assumption that an asset enters service mid-year, so a 5-year asset spreads across six tax years.
- Tax shield:
- Taxable income reduced by depreciation — the deduction multiplied by your marginal rate, valued as a discounted stream.
- Deferred tax:
- The future tax obligation created when book and tax depreciation differ — it reverses as the schedules converge.
Related Concepts
- Book vs tax depreciation: The two schedules businesses run in parallel — their difference is the deferred-tax balance.
- Amortization: The same spreading principle applied to intangible assets; EBITDA calculator adds both charges back.
- Tax shield: Depreciation times the marginal rate — the cash-saving mechanism behind accelerated methods.
- Lease depreciation: In a car lease the depreciation fee drives the monthly payment; our car loan calculator compares buying against leasing.
- Salvage value: The floor under every book schedule — it also anchors resale and trade-in estimates.
Example
A $10,000 machine with a $1,000 salvage value and a 5-year life.
Straight-line: ($10,000 − $1,000) ÷ 5 = $1,800 every year; book value falls 8,200 → 6,400 → 4,600 → 2,800 → 1,000.
Double-declining (factor 2, rate 40%): 4,000 → 2,400 → 1,440 → 864, then the final year plugs to the remaining 296 so the asset lands exactly on the $1,000 floor.
MACRS 5-year ignores salvage and writes the full $10,000 across six tax years: 2,000 → 3,200 → 1,920 → 1,152 → 1,152 → 576. At a 30% tax rate the straight-line schedule shelters $1,800 × 30% = $540 a year — worth $2,156 in today's money at an 8% discount rate. Sell in year 2 for $7,000 against a $6,400 book value and you book a $600 gain.
Interpreting Your Results
Read the first-year deduction first: it is where methods diverge most. Double-declining writes off roughly twice straight-line's amount up front; SYD sits between them; MACRS front-loads hardest because the half-year convention plus 200% declining balance combine in year one.
Then read the curves: in compare mode every book-value line starts at cost and ends at salvage (or zero for MACRS), but accelerated methods bend away sharply in the early years — that gap is the timing benefit. Finally read the shield: a large nominal shield discounted at a high rate is worth less than a smaller late shield at a low rate, so always trust the present value over the total.