The mechanisms that target you most
What the result demonstrates
The number of active contexts isn't a personal risk score — it's a snapshot of how many scenarios a scammer could try against you, each with its own chance of landing. Three of these scenarios have been rigorously quantified elsewhere in this pillar; the other seven broaden your exposure qualitatively, with no invented figure.
Our calculation — the pillar's synthesis
The three quantified scenarios in this pillar each have their own base rate, measured at the population level: receiving a package on a given day (≈5.5%, derived from USPS's 18.6 million daily parcels against the US adult population — see our package demonstration), being unemployed and actively job-hunting (≈4.2%, the US unemployment rate, BLS — see our recruiters demonstration), and having a bank account (≈95.8%, FDIC's most recent National Survey of Unbanked and Underbanked Households — see our banking demonstration).
The formula that runs through this whole pillar — P(at least one scenario true) = 1 − (1 − p₁)(1 − p₂)(1 − p₃) — applied to just these three scenarios already gives 1 − (0.945 × 0.958 × 0.042) ≈ 96%. This is a fact about the general population, not about you personally: it explains why a mass campaign combining these three scenarios statistically reaches almost everyone, with zero targeting.
The other seven questions in the calculator (messaging apps, social media, marketplace buying/selling, travel, bank transfers, dependent children, past data breach notification) have no quantified base rate in this pillar — they broaden your personal surface without an invented figure attached. It's a tally, not a probability.
Limits: this calculator measures no real individual risk — it illustrates a line of reasoning, using base rates drawn from national samples, not an assessment of your personal situation.
The takeaway
Scammers don't need to know you. The statistics already do.
The scam has become bespoke. The protection had to become bespoke too.
Frequently asked questions
What is the Coincidence Surface?
The number of real contexts in your digital life that make a fraudulent message statistically plausible for you at a given moment — without a scammer needing to know any personal data about you.
Does the calculator send my answers anywhere?
No. The calculation runs entirely in your browser. No answer is ever saved, transmitted, or stored.
Why does the result stay high even with few active contexts?
Because a single near-universal context — having a bank account, true for the vast majority of adults — is enough on its own to make a mass campaign statistically effective. The other contexts multiply the number of scenarios a scammer can try, rather than adding an individual probability.
Rigor note. The three base rates used in this calculation (package day ≈5.5%, unemployment ≈4.2%, banked ≈95.8%) are derived consistently with the sourced figures in Demonstrations 1, 2, and 4 of this pillar — they are not recalculated here. The package-day figure is our own derivation from USPS's published daily volume against US Census population estimates, not an officially published percentage — the same methodology used for the equivalent French-language calculator. The unemployment rate is BLS's official figure; the banked rate is FDIC's most recent national survey figure, relayed here rather than re-fetched directly in this pass — marked 🟡 accordingly. The other seven questions are intentionally left unquantified: per our methodology, the absence of a reliable national statistic for these contexts leads us to treat them qualitatively rather than invent a probability. This page adapts the French original (Surface de coïncidence) with US-specific base rates rather than reusing the French ones.
The Mathematics of Manipulation — the pillar
All 9 demonstrations in this pillar, official figures and published assumptions.
Learn more
Egidio — The Threat Laboratory, "Calculate your Coincidence Surface", egidio.app/en/laboratoire/mathematics-of-manipulation/coincidence-surface/. Licensed CC BY 4.0.
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