# Depreciation Calculator: WDV vs SLM, Income Tax Rates > Depreciation calculator: compare WDV and straight-line with income-tax block rates (15%, 40%, 10%, 5%) and the half rate for assets used under 180 days. Source: https://trykosh.com/tools/depreciation-calculator Free tool - Business and GST # Depreciation calculator: WDV and straight line Work out depreciation on a business asset year by year, the income-tax way (written-down value at block rates) and the straight-line way most company books use. Rules checked 25 October 2026Free - no sign-upRuns in your browser Year 1 depreciation (WDV) INR 75,000 15% on INR 5,00,000 WDV total, 6 years**INR 3,11,425** WDV left after 6 years**INR 1,88,575** SLM year 1**INR 47,500** WDV at 15% vs SLM over 10 years Year WDV charge WDV closing SLM charge SLM closing Year 1 INR 75,000 INR 4,25,000 INR 47,500 INR 4,52,500 Year 2 INR 63,750 INR 3,61,250 INR 47,500 INR 4,05,000 Year 3 INR 54,188 INR 3,07,063 INR 47,500 INR 3,57,500 Year 4 INR 46,059 INR 2,61,003 INR 47,500 INR 3,10,000 Year 5 INR 39,150 INR 2,21,853 INR 47,500 INR 2,62,500 Year 6 INR 33,278 INR 1,88,575 INR 47,500 INR 2,15,000 Income tax depreciates a whole block of similar assets at one WDV rate. Assets added and used for under 180 days in a year get half the rate that year; the rest comes later. ## Upload your statement and Kosh does this for you. Upload your bank statements and Kosh separates business from personal spending and keeps your tax and GST dates in view. [Start free](/signup?via=tool-depreciation-calculator) ## How the depreciation calculator works Income tax depreciates assets in blocks at fixed written-down value (WDV) rates. Each year the rate applies to what's left of the block, so the charge is highest in year one and shrinks after. The common rates: 15% for plant and machinery (including cars not used for hire), 40% for computers and software, 10% for furniture and fittings, 10% for office and factory buildings, 5% for residential buildings, 30% for vehicles used in a hire business, and 25% for intangibles such as patents and licences. If an asset is put to use for less than 180 days in the year you buy it, only half the rate is allowed that year. The rest isn't lost: the higher closing value carries into next year's charge. The calculator applies this when you tick the box. Straight-line (SLM) spreads the cost, less any residual value, evenly over the useful life. Companies follow the useful lives in Schedule II of the Companies Act, for example three years for laptops and fifteen for general plant, with residual value usually up to 5% of cost. SLM is for your books; your tax return still uses WDV. Choose 'compare' to see both side by side. The difference between book and tax depreciation is why company accounts carry deferred tax, and why a proprietor's tax profit and book profit differ. WDV: depreciation = opening value x rate (half in year 1 if used < 180 days); SLM: (cost − residual) / useful life Opening value cost less depreciation already claimed ## Worked example: Vikram's CA firm buys laptops in November Vikram's firm buys INR 6 lakh of laptops in November 2026, so they're used for less than 180 days before 31 March. Income tax allows half of 40%: INR 1,20,000 in FY 2026-27. The next year's charge is 40% of INR 4,80,000, or INR 1,92,000. After four years INR 1,03,680 remains in the block. In his books, straight-line over three years with a INR 30,000 residual gives INR 1,90,000 a year. Year 1 depreciation (WDV) INR 1,20,000 40% on INR 6,00,000, halved for under 180 days WDV total, 4 years**INR 4,96,320** WDV left after 4 years**INR 1,03,680** SLM year 1**INR 1,90,000** Income tax depreciates a whole block of similar assets at one WDV rate. Assets added and used for under 180 days in a year get half the rate that year; the rest comes later. [Load this example into the calculator ->](?cost=600000&block=computer&half=1&life=3&salvage=30000&years=4#calculator) ## Good to know - Selling an asset reduces the block, not a separate asset. If sale proceeds exceed the block's value, the excess is taxed as short-term capital gain. - New plant and machinery for manufacturing can get additional depreciation of 20% in the first year (10% if used under 180 days). It isn't available to individuals in the new regime or to companies in the 22% and 15% concessional regimes. - Land is never depreciated, only the building on it. Split the cost of a property between the two. - Under the 44AD or 44ADA presumptive schemes, depreciation is deemed to be allowed already: you can't claim it separately, but the asset's WDV is reduced as if it had been. ## Frequently asked questions What is the depreciation rate on computers under income tax? 40% on the written-down value, which covers computers, laptops and computer software. If bought and used for less than 180 days in the year, only 20% is allowed in that first year. What is the difference between WDV and SLM? WDV applies a fixed percentage to the remaining value each year, so the charge falls over time and never quite reaches zero. SLM charges the same amount every year until the asset reaches its residual value. Income tax uses WDV; company books often use SLM. What is the 180-day rule for depreciation? If an asset is acquired during the year and put to use for less than 180 days in that year, only half the normal depreciation rate is allowed for that year. The full rate applies from the next year on the reduced value. Can I claim depreciation on a car used for business? Yes, at 15% on WDV, in proportion to business use. Cars used in a taxi or hire business qualify for 30%. Keep a log of business use, as personal use reduces the claim. Is depreciation allowed under the presumptive scheme? Not separately. Under 44AD and 44ADA the deemed profit already allows for all expenses, depreciation included. For later years, the asset's written-down value is calculated as if depreciation had been claimed. ## Sources and assumptions - [Income Tax Department](https://www.incometax.gov.in/) Rules and rates last checked on 25 October 2026. Results are estimates for planning and education, not tax, legal or investment advice. Kosh is an educational financial planning tool by Primedepth Labs. It is not a SEBI-registered investment adviser and does not offer personalised investment advice, hold your money or execute trades. Markets carry risk; read scheme documents carefully and consult a registered adviser before acting.