The formula
Impact = (Payables − Receivables) × (1 − Hedged%/100) × Move%/100
Netting comes first because payables and receivables in the same currency offset naturally: a rate move that makes your supplier invoice dearer makes your customer receipt worth more. Only the net imbalance is true exposure — businesses that hedge gross payables while holding receivables in the same currency pay to hedge risk they do not have.
The adverse-move input is a scenario, not a forecast. A useful discipline is to use a move the pair has actually produced within your exposure window — the worst 90-day move of the last three years, for example — rather than a comfortable round number.
How to use this calculator
- 1
Total open payables
Every unpaid invoice denominated in the foreign currency, regardless of due date, plus committed orders not yet invoiced if you want the full picture.
- 2
Total open receivables
Customer invoices and confirmed inflows in the same currency over the same window.
- 3
Enter what is already hedged
Forwards, rate holds or pre-purchased currency as a percentage of the net position.
- 4
Choose an honest scenario
Look at what the pair has actually done over your exposure horizon and test that, not a hopeful number.
From measurement to policy
A single measurement is a snapshot; a policy is a rule that survives busy quarters. The most common SME policy is threshold-based: exposures under a floor (say $25,000) run open, exposures above it are hedged to a fixed ratio (say 50–80%), and the ratio rises as the invoice date approaches. The right numbers depend on your margin — a distributor on 8% gross margin cannot absorb a 5% adverse move on a large invoice; a 60%-margin software exporter can.
Frequency matters as much as thresholds. Exposure should be re-measured on a schedule — monthly for most SMEs, weekly for import-heavy businesses in volatile-currency markets — because exposure changes every time an invoice is raised, paid or received. The measurement itself takes minutes once payables and receivables are listed by currency.
The invoicing-currency lever
Exposure is negotiable before it exists. The currency an invoice is denominated in decides who carries the risk: a Ghanaian importer invoiced in USD carries the GHS/USD exposure; the same goods invoiced in GHS move that exposure to the supplier — who will price it into the invoice. Neither side escapes the risk; invoicing currency decides who manages it and at what embedded cost.
Suppliers with treasury capability often price currency risk more cheaply than a small importer can hedge it — sometimes the USD invoice plus your own hedge beats the local-currency invoice with the supplier’s buffer built in. The Academy guide on invoice FX exposure works through that comparison; this calculator gives you the exposure number the comparison starts from.
Common use cases
Monthly exposure review
Re-measure net open exposure per currency as invoices are raised and settled.
Hedge sizing
Decide how much of the net position to cover once you can see it in one number.
Margin protection
Test whether a realistic adverse move would erase the margin on a large order.
Board and lender reporting
Report FX risk as a measured figure with a scenario, not a qualitative worry.
Automate this with the API
Benchmark a live indicative rate against the rate your exposure was booked at.
curl "https://keybs.io/api/v1/tools/fx?from=USD&to=NGN&amount=50000" \ -H "x-api-key: YOUR_FREE_KEY"Free Tools API docs and key registration
Frequently asked questions
Should I hedge gross payables or the net position?
Net, in almost all cases. Payables and receivables in the same currency offset naturally, and hedging gross means paying hedging costs on risk that cancels itself. The exception is when the timing mismatch between payables and receivables is so large that they do not effectively overlap.
What counts as exposure besides unpaid invoices?
Committed purchase orders not yet invoiced, foreign-currency cash balances, foreign-currency loans, and recurring obligations like payroll or rent abroad. Start with invoices — they dominate for most SMEs — then widen the net as the discipline settles.
How do I pick the adverse-move percentage?
Use realised history for your pair over your exposure window: the worst 60- or 90-day move of the past three years is a defensible stress. Volatile emerging-market pairs can move double digits in a quarter; major pairs usually less. Testing two scenarios — typical and severe — brackets the decision.
Is holding a foreign-currency balance a hedge?
Holding the currency you will need to pay suppliers is a genuine hedge for those payables — you have pre-purchased the exposure. It costs opportunity and possibly interest differential, but removes rate risk on the covered amount. Multi-currency accounts make this practical; enter pre-held balances in the hedged percentage.
At what size does FX exposure deserve formal attention?
A workable rule: when a plausible adverse move on your net exposure exceeds what you would happily lose on a bad week of trading, it deserves a policy. For many importers that threshold arrives around $50,000–$100,000 of net exposure in a volatile pair.
How does KeyBS Pay help manage exposure?
Quote-first pricing removes rate surprise at execution: the rate, the fee (from 1.5%, route-dependent) and the receive amount are committed before you approve. Global Business Accounts support holding and netting across currencies so receivables can fund payables without a round trip through conversion. Availability is route-dependent.
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