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TQB/ learn/ rates/ interest rate swapsEN · DARK
IRpractitionerinstrument

Interest Rate Swaps

Exchange fixed coupons for floating-rate cashflows.

Reviewed 2026-08-10TheQuantBateman Research1 linked labs
01Intuition

Build the mental model first.

The par swap rate makes the fixed leg equal the floating leg at inception.

ONE-LINE DEFINITION

Exchange fixed coupons for floating-rate cashflows.

02Mathematics

Now make it exact.

Kpar=P(0,T0)P(0,Tn)iδiP(0,Ti)K_{par}=\frac{P(0,T_0)-P(0,T_n)}{\sum_i \delta_iP(0,T_i)}
Notation and units

Decimal rates and volatilities, year-fraction time and continuous compounding unless stated otherwise.

03Assumptions

Every model has a price.

01

Educational conventions are stated explicitly and may simplify market quotation or settlement details.

02

Rates are continuously compounded unless the section says otherwise.

03

Inputs are deterministic in the base model.

“An unstated convention is a future reconciliation break.”— THEQUANTBATEMAN
04Market use

Why a quant cares.

Benchmark rate exposure, curve calibration and asset-liability hedging.

IntuitionMathematicsImplementationDesk risk
05Desk view
FRONT OFFICE VIEW

The hedge has opinions.

Start with the quote convention, then ask which IR risk survives the hedge. A number without its convention is merely well-dressed ambiguity.

Ask Bateman about this model
06Related

Continue through the graph.