Swaption Calculator — Price Payer & Receiver Swaptions

The forward swap rate and annuity come straight off our current par curve — the same broker-sourced data the major terminals use and our swap-rate pages show. The premium is then Bachelier (normal model), market convention for European swaptions, priced at the volatility you set on the slider — see the swaption volatility surface for why that input matters. Indicative levels: annual grid, bullet notional, whole-year expiries, mid rates. The app prices exact dates, any strike, off the live vol surface. Certain financing rather than probable? Price the swap instead with the swap calculator.

As of 7 August 2026, the 1Y×5Y USD forward swap rate is 4.15% (live, off our current curve). A developer expecting to draw $10m of floating-rate debt in a year buys a payer swaption struck there: at a 90bp vol assumption the premium is 1.55% of notional — $155,114 — with a delta of 0.50, DV01 of $2,160 and vega of $1,723 per vol bp. If 5Y rates are above the strike next year, the developer exercises and pays fixed at below-market; if they have fallen, it walks away and the premium was the cost of a year of certainty. New to swaptions? Start with the guide. These numbers re-run from each curve snapshot.

The premium depends on five things: the forward swap rate, the strike, the option expiry, the tenor of the underlying swap, and implied volatility. At the money, a useful mental model is that the premium scales with volatility, the square root of expiry, and the annuity of the underlying swap — so a 1-year option into a 5-year USD swap costs on the order of 1 to 2% of notional in recent conditions, and a 5-year option into a 10-year swap several times that. The calculator above prices your exact structure off the live forward, at a volatility assumption you control.

Market convention prices European swaptions with the Bachelier (normal) model — the rates-market cousin of Black-Scholes, comfortable with rates near or below zero. The inputs are the forward swap rate, the strike, time to expiry, the annuity of the underlying swap, and the normal implied volatility in basis points, read off the swaption volatility surface for that expiry and tenor. The formula is the easy part — the live curve, the live vols and the annuity conventions are what a pricing tool has to get right.

Because the live swaption volatility surface is licensed market data, available in the BlueGamma app. Everything else on this calculator is live — the forward swap rate and annuity come off our current curve, from the same broker sources the terminals use. The vol slider makes the one missing input explicit, and the sensitivity to the surface shows exactly how much it matters. In the app the surface is read for you, per expiry and tenor, and updates through the day.

Yes — BlueGamma prices payer and receiver swaptions off live curves and the live normal vol surface, returning premium, forward rate, vol, delta, DV01 and vega in Excel with one function or via the pricing API. It ships with the 14-day free trial.