Weighted Price Index Calculator
Build a base-100 Laspeyres, Paasche or Fisher price index from your own item rows.
L = Σ(pt × q0) / Σ(p0 × q0); P = Σ(pt × qt) / Σ(p0 × qt); F = √(L × P); I = 100 × {L, P, F}
Keep item units, quality and periods consistent. Prices and quantities must be nonnegative; each required weighted base-price sum must be positive. This textbook index is not an official CPI. No official data or files are imported.
All calculations run locally in your browser.
Independent implementation and original explanatory text. The ILO manual is linked as a formula reference; its text and data are not reproduced, and no license to reuse the manual is asserted.
A QUICK WALKTHROUGH
How to use this tool
- Enter item names, base and current prices and quantities. Choose an index method, then calculate.
- Keep item units, quality and periods consistent. Prices and quantities must be nonnegative; each required weighted base-price sum must be positive. This textbook index is not an official CPI. No official data or files are imported.
Formula
L = Σ(pt × q0) / Σ(p0 × q0); P = Σ(pt × qt) / Σ(p0 × qt); F = √(L × P); I = 100 × {L, P, F}
Input basis
Keep item units, quality and periods consistent. Prices and quantities must be nonnegative; each required weighted base-price sum must be positive. This textbook index is not an official CPI. No official data or files are imported.
Processing and attribution
All calculations run locally in your browser. Independent implementation and original explanatory text. The ILO manual is linked as a formula reference; its text and data are not reproduced, and no license to reuse the manual is asserted. https://webapps.ilo.org/CPI/doc/cpi_manual_en.pdf
GOOD TO KNOW
Common questions
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All calculations run locally in your browser.