What you can calculate in this section
Calculate depreciation expense and book value using clearly defined methods and estimates. Start with the result you need, then confirm that every input comes from the same period and uses the definition shown on the selected page.
A calculator returns a mathematical result. The worked example and limitations explain whether that result belongs in the decision you are making.
3 guides and calculators
Each page below gives the direct definition first, then the equation or method, inputs, sample calculation, common mistakes and related formulas.
Double Declining Depreciation Formula
double declining depreciation formula explained with the formula, inputs, example and limitations.
Open Double Declining Depreciation Formula →Straight Line Depreciation Formula
straight line depreciation formula explained with the formula, inputs, example and limitations.
Open Straight Line Depreciation Formula →Depreciation Formula
depreciation formula explained with the formula, inputs, example and limitations.
Open Depreciation Formula →How to choose the right formula
- Name the decision.
Decide whether you need a value, rate, margin, return, balance or comparison. - Match the timing.
Use annual figures with annual figures and distinguish a point-in-time balance from a period flow. - Check the definition.
Confirm what each numerator, denominator, cash flow or cost includes. - Run an example.
Reproduce the sample result before entering your own figures. - Test another case.
Change one assumption at a time and record what drives the answer.
Frequently asked questions
What is depreciation formulas?
Calculate depreciation expense and book value using clearly defined methods and estimates.
How should I use depreciation formulas?
Use the formula only after matching every input to the same period, unit and definition. Then compare the result with a worked example and the decision you are trying to make.
What is the most common mistake with depreciation formulas?
The most common mistake is choosing a familiar formula before defining the decision, period, units and available inputs.
Can I calculate depreciation formulas in a spreadsheet?
Yes. Reproduce the displayed equation with separate cells for each input, keep percentages as decimals, and test the spreadsheet against the worked example before replacing the sample figures.
Sources and methodology
The section’s financial context is checked against IAS 16 Property, Plant and Equipment. Each leaf page names the source used for its specific formula or reporting relationship.