Cross-Price Elasticity Calculator

In 2026, a pricing analyst at a CPG company in Cincinnati needs to defend a 4% price increase on a flagship brand to the marketing team. The question they will be asked: how much will Tide volume fall if Persil cuts prices by the same? The answer requires cross-price elasticity — measured here, plotted on the cross-plot, and used in every IRI/Nielsen pricing study run on retail scanner data.

The concept of cross-price elasticity originates with Alfred Marshall's 1890 Principles of Economics, which introduced "elasticity of demand" as a unit-free measure of responsiveness. Marshall's student Arthur Pigou extended the framework to handle multiple products. The formal distinction between substitute and complement goods comes from John Hicks's 1939 Value and Capital, which built on Eugen Slutsky's 1915 paper in Russian (only translated to English in 1953).

Empirical estimation of cross-price elasticity advanced dramatically with the arrival of scanner data in the 1980s. IRI (Information Resources Inc., now part of NIQ) and Nielsen began aggregating store-level price-quantity data weekly. Berry, Levinsohn and Pakes (BLP) introduced their random-coefficient logit demand model in 1995 — the gold standard for estimating cross-price elasticity today. The 2014 Nobel Prize to Jean Tirole acknowledged this stream of industrial organization research.

Regulators have used cross-price elasticity to define markets since the US Department of Justice's 1982 Merger Guidelines. The Horizontal Merger Guidelines (2010 update, jointly issued by DOJ and FTC) operationalize the SSNIP test — small significant non-transitory increase in price. If a 5% price rise is unprofitable because demand shifts to a candidate substitute (high E_xy), that substitute is in the same market. Used to block AT&T-T-Mobile (2011), let through AT&T-Time Warner (2018), and approved Microsoft-Activision (2024).

The SEC requires registered investment advisers to disclose investment risks from substitution dynamics under Form ADV. Equity research analysts at major broker-dealers (Goldman Sachs, Morgan Stanley, JPMorgan) routinely publish cross-price elasticity estimates in industry primers — particularly in CPG, telecom, streaming, and retail-discount sectors. The CFA Institute's Level II Microeconomics reading covers elasticity in detail.

By 2026 the gold-standard scanner-data source is the NielsenIQ + IRI combined Circana database, covering 95% of US retail UPCs across 30,000+ stores. Demand estimation tools (Profitero, Aforza, Vendavo) embed BLP-style cross-price elasticity engines for product-line pricing. The widget on this page is a simplified version — appropriate for back-of-envelope decisions, not for quarterly board meetings.

The IFRS treatment of price elasticity for revenue forecasting falls under IFRS 15 (revenue from contracts). Companies must consider price-sensitivity assumptions when estimating variable consideration. The FASB's ASC 606 mirrors IFRS 15. Both standards require quantitative price-sensitivity inputs in revenue forecasts published in 10-Ks — making the math on this page directly relevant to public filings.