Depreciation calculator for India (Companies Act and Income-tax Act)

Useful life (typical for the Companies Act)

With SLM, the yearly charge is the cost minus the residual value, divided by the useful life. With WDV, the calculator works out the rate that brings the cost down to the residual value over the useful life, and applies it to each year's opening value:

WDV needs a residual value above zero; with zero the formula would give a 100% rate. In the last year of the useful life, the calculator charges whatever is left so the closing value lands exactly on the residual value.

Rate (typical for the Income-tax Act)

With WDV, each year's depreciation is the rate times the opening value, so the value keeps falling but never reaches zero. That is why you choose how many years to show. With SLM and a rate, the rate is applied to the original cost every year until the value reaches the residual value.

First year

• Pro rata by days: the first year's charge is multiplied by the days used (from the put-to-use date to 31 March) divided by the days in that financial year (365, or 366 when it includes 29 February). Schedule II of the Companies Act calculates depreciation pro rata from the date of addition.
• Half rate if used under 180 days: if the asset was used for fewer than 180 days in its first financial year, it gets half the normal depreciation that year, and the full rate after that. This is the Income-tax rule in section 32(1) of the 1961 Act and section 33(4) of the Income-tax Act, 2025.
• Full year: no adjustment, for when you want a simple annual schedule.

Rounding

Each year's depreciation is rounded to the nearest paisa, and the next year starts from the rounded closing value, so the table always adds up.

Check it against a worked example

Cost ₹1,00,000, put to use 1 October 2025, Companies Act preset for laptops (3 years, SLM, 5% residual). The first year has 182 of 365 days, so depreciation is ₹31,666.67 × 182 ÷ 365 = ₹15,789.95, then ₹31,666.67 for two full years and ₹15,876.71 in 2028-29, ending at ₹5,000. Switch to the Income-tax computers preset with the date 15 November 2025 and you get ₹20,000 (half rate, only 137 days), then ₹32,000 and ₹19,200.

What it does not do

• It works on one asset. The Income-tax Act applies rates to a whole block of assets, including additions and sales during the year, so your actual tax depreciation is calculated on the block.
• It does not include additional depreciation for new plant and machinery, extra-shift depreciation under Schedule II, or sale and disposal entries.
• It is general information, not tax advice. Check the final numbers with your CA.

For the rules behind these numbers, with official sources, read Depreciation under the Companies Act vs the Income-tax Act. To set up the register these figures come from, see the fixed asset register format.

A calculator is fine for one laptop. For a few hundred assets across branches, Assets Tracker calculates depreciation as per the Income-tax Act and the Companies Act from your asset register (Growth plan and above), and exports it to Excel or PDF for your CA. The same register carries photos, QR labels, custodians, warranty and AMC reminders, and physical audits by scanning. Read how it works for offices and CA firms, factories, schools and hospitals, or हिंदी में पढ़ें.