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

# Read a tax calculation

> Returns one stored calculation: the lines as they were submitted joined with the engine's answer for each, plus the invoice it was issued into when it has been. A calculation stays readable after it expires or is issued from, so this is the audit record behind an invoice's tax. Read it back with the `tax_calculation_id` returned on the invoice.



## OpenAPI

````yaml /api-reference/v2/specs/2026-04-01.json get /tax/calculations/{id}
openapi: 3.1.0
info:
  title: Alguna Public API
  version: '2026-04-01'
servers:
  - url: https://api.alguna.io
security:
  - bearerAuth: []
tags:
  - name: Billing Events and Metrics
  - name: Checkout Sessions
  - name: Credit Notes
  - name: Credits
  - name: Customer Portal Sessions
  - name: Customers
  - name: Insights
  - name: Integrations
  - name: Invoices
  - name: Payments
  - name: Plans
  - name: Product Bundles
  - name: Products
  - name: Refunds
  - name: Revenue Schedules
  - name: Subscription Changes
  - name: Subscription Versions
  - name: Subscriptions
  - name: Tax
  - name: Wallet Grants
  - name: Wallets
paths:
  /tax/calculations/{id}:
    get:
      tags:
        - Tax
      summary: Read a tax calculation
      description: >-
        Returns one stored calculation: the lines as they were submitted joined
        with the engine's answer for each, plus the invoice it was issued into
        when it has been. A calculation stays readable after it expires or is
        issued from, so this is the audit record behind an invoice's tax. Read
        it back with the `tax_calculation_id` returned on the invoice.
      operationId: get-tax-calculation
      parameters:
        - in: header
          name: Alguna-Version
          required: true
          schema:
            enum:
              - '2026-04-01'
            type: string
        - in: path
          name: id
          required: true
          schema:
            description: Unique identifier for the calculation
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TaxCalculationDetailResponse'
          description: Success
        '400':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
          description: Bad Request
        '401':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
          description: Unauthorized
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
          description: Not Found
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
          description: Unprocessable Entity
        '500':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
          description: Internal Server Error
components:
  schemas:
    TaxCalculationDetailResponse:
      properties:
        consumed_at:
          description: >-
            When an invoice was issued from this calculation; a calculation
            issues once
          format: date-time
          nullable: true
          type: string
        created_at:
          description: When the calculation was made
          format: date-time
          type: string
        currency:
          description: Currency of the amounts
          example: USD
          type: string
        customer_reference:
          description: >-
            Your own id for the buyer, as sent; absent when the calculation was
            for a guest
          nullable: true
          type: string
        expired:
          description: Whether the calculation can no longer be issued from
          type: boolean
        expires_at:
          description: When the calculation stops being issuable
          format: date-time
          type: string
        id:
          description: Id of the calculation
          type: string
        invoice_id:
          description: Invoice this calculation was issued into, when it has been
          nullable: true
          type: string
        legal_entity_id:
          description: Selling legal entity whose tax engine produced the calculation
          type: string
        line_items:
          description: Per-line breakdown behind the total
          items:
            $ref: '#/components/schemas/TaxCalculationDetailLineResponse'
          type: array
        tax_date:
          description: >-
            Date tax was assessed on; an invoice issued from this calculation is
            taxed as of this date
          format: date-time
          type: string
        total_tax:
          description: Sum of per-line tax amounts
          example: '6.60'
          type: string
      required:
        - created_at
        - currency
        - expired
        - expires_at
        - id
        - legal_entity_id
        - line_items
        - tax_date
        - total_tax
      type: object
    ErrorResponse:
      properties:
        detail:
          type: string
        status:
          format: int64
          type: integer
      required:
        - status
        - detail
      type: object
    TaxCalculationDetailLineResponse:
      properties:
        amount:
          description: Per-unit amount sent for this line
          example: '100.00'
          type: string
        billing_period_end:
          description: End of the service period sent for this line, exclusive
          format: date-time
          nullable: true
          type: string
        billing_period_start:
          description: Start of the service period sent for this line, inclusive
          format: date-time
          nullable: true
          type: string
        description:
          description: Description sent for this line
          type: string
        quantity:
          description: Quantity sent for this line
          example: '1'
          type: string
        reference:
          description: Reference sent for this line (or the generated one)
          type: string
        tax_amount:
          description: Tax amount for the line
          example: '6.60'
          type: string
        tax_code:
          description: Canonical tax code the line was taxed under
          nullable: true
          type: string
        tax_rate:
          description: >-
            Combined tax rate applied across jurisdictions, as a percentage
            (8.25 = 8.25%)
          example: '8.25'
          type: string
        tax_reason:
          description: Reason determining how tax was applied
          nullable: true
          type: string
        tax_type:
          description: Type of tax applied
          nullable: true
          type: string
        taxable_amount:
          description: Portion of the line the tax rate was applied to
          example: '80.00'
          type: string
      required:
        - amount
        - quantity
        - tax_amount
        - tax_rate
        - taxable_amount
      type: object
  securitySchemes:
    bearerAuth:
      bearerFormat: API Key
      description: API key authentication. Pass your API key as a Bearer token.
      scheme: bearer
      type: http

````