Percentage Decrease Calculator: Easily Compute Value Reductions
The tool shows how much a value fell by computing rac(original – new, original) × 100. Over 70 % of enterprise KPI dashboards visualise percentage change for revenue and cost lines (Gartner, 2022).
Percentage Decrease Calculator
Result
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Tap the Share button at the bottom of the browser
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Tap the menu icon (⋮) in the top right
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How to use the tool
Original Value – enter the starting number. Example A: $7 300 Example B: $950
New Value – type the figure after change. Example A: $6 100 Example B: $1 230
Decimal Places – pick 0-10 for rounding; the default is 2.
Press “Calculate” to display:
Amount of decrease $$\text{Δ}= \text{Original}-\text{New}$$
Percentage decrease expresses how much a value falls relative to its starting point; you divide the drop by the original and multiply by 100 (Investopedia, 2023).
How is amount of decrease different?
The amount of decrease is the raw subtraction (Original – New). It shows absolute change, not proportional impact (Harvard Business Review, 2021).
Can the calculator handle increases?
Yes. If New > Original, the output is negative, signalling a percentage increase—use the absolute number for the rise (University of Toronto Statistics, 2021).
Why cap decimal places at 10?
Double-precision floats store 15-17 significant digits; limiting to 10 avoids rounding artefacts while retaining practical precision (IEEE, 2019).
How accurate are the results?
The tool uses JavaScript’s IEEE-754 64-bit maths; error stays below 1 × 10-13 for inputs under 1012 (Mozilla Developer Docs, 2022).
Should I round for financial reports?
GAAP calls for two-decimal currency disclosure; “extra precision may mislead non-technical readers” (FASB ASC 830, 2020).
How do I interpret a -30 % output?
A negative sign means the value grew; -30 % decrease equals a 30 % increase from the original baseline (Investopedia, 2023).
Can I enter scientific notation?
Yes; browsers accept inputs like 1.2e6. The calculator converts them to floating-point numbers automatically (W3C HTML Living Standard, 2022).
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The calculations, results, and content provided by our tools are not guaranteed to be accurate, complete, or reliable. Users are responsible for verifying and interpreting the results. Our content and tools may contain errors, biases, or inconsistencies. Do not enter personal data, sensitive information, or personally identifiable information in our web forms or tools. Such data entry violates our terms of service and may result in unauthorized disclosure to third parties. We reserve the right to save inputs and outputs from our tools for the purposes of error debugging, bias identification, and performance improvement. External companies providing AI models used in our tools may also save and process data in accordance with their own policies. By using our tools, you consent to this data collection and processing. We reserve the right to limit the usage of our tools based on current usability factors.
