> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fincept.in/llms.txt
> Use this file to discover all available pages before exploring further.

# Black76 Swaption Price

> Price a European swaption using the Black76 model. A swaption is an option to enter into an interest rate swap.

**Types:**
- **Payer Swaption**: Right to enter a swap as fixed-rate payer (benefits when rates rise)
- **Receiver Swaption**: Right to enter a swap as fixed-rate receiver (benefits when rates fall)

**Use Cases:**
- Price exchange-traded and OTC swaptions
- Hedge future swap positions
- Manage interest rate exposure for future borrowings
- Value embedded options in callable/putable bonds

**Tier:** Standard (2 credits/request) [Tier: PRO, Credits: 5]



## OpenAPI

````yaml api-specs/pricing.json post /quantlib/pricing/black76/swaption
openapi: 3.1.0
info:
  title: FinceptQuantLib API - Pricing Module
  description: >-
    Advanced options pricing models including Black-Scholes, Black76, Bachelier,
    Kirk spread options, and binomial trees. Standard Tier access required (2
    credits per request).
  version: 3.0.0
  contact:
    name: Fincept API Support
    url: https://fincept.in
servers:
  - url: https://api.fincept.in
    description: Fincept API Production Server
security:
  - APIKeyHeader: []
tags:
  - name: quantlib-pricing
    description: Advanced options pricing models and Greeks calculation
    x-displayName: Pricing
paths:
  /quantlib/pricing/black76/swaption:
    post:
      tags:
        - quantlib-pricing
      summary: Black76 Swaption Price
      description: >-
        Price a European swaption using the Black76 model. A swaption is an
        option to enter into an interest rate swap.


        **Types:**

        - **Payer Swaption**: Right to enter a swap as fixed-rate payer
        (benefits when rates rise)

        - **Receiver Swaption**: Right to enter a swap as fixed-rate receiver
        (benefits when rates fall)


        **Use Cases:**

        - Price exchange-traded and OTC swaptions

        - Hedge future swap positions

        - Manage interest rate exposure for future borrowings

        - Value embedded options in callable/putable bonds


        **Tier:** Standard (2 credits/request) [Tier: PRO, Credits: 5]
      operationId: black76_swaption
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SwaptionRequest'
            example:
              forward_swap_rate: 0.04
              strike: 0.045
              annuity: 4.5
              volatility: 0.18
              t_expiry: 2
              is_payer: true
              notional: 1000000
      responses:
        '200':
          description: Successful calculation
          content:
            application/json:
              schema:
                type: object
                properties:
                  success:
                    type: boolean
                    example: true
                  data:
                    type: object
                    properties:
                      swaption_price:
                        type: number
                        description: Swaption price
                        example: 12345.67
                      is_payer:
                        type: boolean
                        description: True for payer swaption, false for receiver
                        example: true
        '401':
          $ref: '#/components/responses/UnauthorizedError'
        '402':
          $ref: '#/components/responses/InsufficientCreditsError'
        '422':
          $ref: '#/components/responses/ValidationError'
components:
  schemas:
    SwaptionRequest:
      type: object
      required:
        - forward_swap_rate
        - strike
        - annuity
        - volatility
        - t_expiry
      properties:
        forward_swap_rate:
          type: number
          description: Forward swap rate (decimal format)
          example: 0.04
        strike:
          type: number
          description: Strike rate of the swaption (decimal format)
          example: 0.045
        annuity:
          type: number
          description: Present value of a basis point (PVBP) or annuity
          example: 4.5
        volatility:
          type: number
          description: Annualized swap rate volatility (decimal format)
          example: 0.18
        t_expiry:
          type: number
          description: Time to expiration in years
          example: 2
        is_payer:
          type: boolean
          description: True for payer swaption, false for receiver swaption
          example: true
          default: true
        notional:
          type: number
          description: Notional amount
          example: 1000000
          default: 1
  responses:
    UnauthorizedError:
      description: Authentication information is missing or invalid
      content:
        application/json:
          schema:
            type: object
            properties:
              detail:
                type: string
                example: Invalid API key
    InsufficientCreditsError:
      description: Insufficient API credits for this request
      content:
        application/json:
          schema:
            type: object
            properties:
              detail:
                type: string
                example: >-
                  Insufficient credits. This endpoint costs 2 credits per
                  request.
    ValidationError:
      description: Request validation failed
      content:
        application/json:
          schema:
            type: object
            properties:
              detail:
                type: array
                items:
                  type: object
                  properties:
                    loc:
                      type: array
                      items:
                        type: string
                    msg:
                      type: string
                    type:
                      type: string
  securitySchemes:
    APIKeyHeader:
      type: apiKey
      in: header
      name: X-API-Key
      description: >-
        API key for authentication. Get your key at
        https://api.fincept.in/auth/register

````