If your biggest supplier failedtomorrow, could you survive?

You enter your annual spend by supplier and, ideally, whether each supplier is locked under a long-term contract. The gate computes each supplier's share of your total spend, scores your supply base 0–100 (driven mainly by your single largest supplier), and returns a per-supplier verdict — SECURED, EXPOSED, or SINGLE-SOURCE RISK — plus a supply-base rollup (SUPPLY SECURE / WATCH THE BASE / SUPPLY-SHOCK RISK) and the one thing to fix first. It answers the question a customer-concentration check doesn't: if your biggest supplier reprices, changes terms, gets acquired, or fails, are you exposed to a day-one crisis?

Because a supplier failure is operationally worse than a customer loss. Lose a big customer and revenue dips next quarter; lose a critical supplier and you may not be able to make the product at all — that's a crisis on day one. Buyers and lenders reflect this: where a single customer above 25–30% of revenue draws scrutiny, a single supplier is commonly flagged at 15–20% of spend. The gate uses that lower line — the supply-security score reaches zero by the time one supplier hits about 30% of spend, tighter than a customer-concentration curve.

Because the contract is what converts a raw percentage into a managed risk. A supplier that's 30% of your spend but locked under a multi-year fixed-terms contract can't reprice or walk away on short notice — that dependency is managed. An 18% supplier on a handshake can vanish next month. So the single-source survival gate fires only when a supplier is BOTH material (over the diligence line) AND uncontracted. Lock a material supplier under a contract and the gate releases — the score still reflects the concentration, but it's no longer a single point of failure. That's the supplier-specific honesty: the percentage alone doesn't tell you whether you're actually exposed.

It degrades gracefully. Leave the contract field blank for a supplier and the gate runs in threshold mode — it can't test the contract half, so it conservatively flags any single supplier at or above the 18% line on share alone (the same line acquirers and lenders use) and tells you it did. The qualified-alternate field is optional too: mark it only when you genuinely have a ready second source you could switch to without a long requalification, and the gate relaxes the material line a little for that supplier. Leave it blank and the gate won't soften a verdict it can't justify.

It's the deliberate mirror. The Customer-Concentration Risk Gate asks 'if your biggest customer left, could you survive?' This asks the same question about the other side of the business — your suppliers. They share the computed-from-numbers shape (shares of a total, a worsen-only survival gate, a portfolio rollup) so the pair reads as one risk lens, but the supplier version uses the lower diligence line and adds the contract as the release valve, because supply risk behaves differently from revenue risk. Run both before a raise, an acquisition, or a lender review — diligence teams check both.

No to both. It's a deterministic, offline planning aid — it computes concentration from the numbers you type, connects to nothing, contacts no supplier, audits no contract, and doesn't assess any supplier's solvency or value your company. It is not financial, accounting, investment, or legal advice and guarantees no valuation, lending, or deal outcome. It flags where your supply base is structurally exposed so you can confirm true switching costs, contract terms, and break-even impact with your own finance and operations read. You get a runnable engine, a workbook that reproduces it, a concentration-audit playbook, a de-risking runbook, and a six-supplier worked sample.