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

# Altcoin Season Index

> Returns the current and previous Altcoin Season Index values with their classification.<br/><br/>Available from&#58; <Badge color="gray">Sandbox</Badge><br/>Cost&#58; <Badge color="surface">1 credit per request</Badge>

<Note>
  Index ≥ 75 - Altcoin Season; 26–74 - Neutral; ≤ 25 - Bitcoin Season.
</Note>


## OpenAPI

````yaml https://api.cryptorank.io/v3/documentation-json get /v3/global/altcoin-index
openapi: 3.0.0
info:
  title: Cryptorank API V3
  description: >
    # Overview


    Cryptorank Public API v3 — comprehensive cryptocurrency data for B2B clients
    and partners.


    Useful Links:

    - [API Plans](https://cryptorank.io/public-api)

    - [Dashboard](https://cryptorank.io/public-api/dashboard)


    # Getting Started


    Primary Server URL:
    [https://api.cryptorank.io/v3/](https://api.cryptorank.io/v3/)


    **Authentication**


    Generate an API key in the
    [dashboard](https://cryptorank.io/public-api/dashboard) and pass it in the
    `X-Api-Key` header.


    Keep your keys secret — never commit them to public repositories or expose
    them in client-side code.
  version: 3.0.0
  contact:
    name: Cryptorank Team
    url: https://cryptorank.io
    email: info@cryptorank.io
servers:
  - url: https://api.cryptorank.io
security: []
tags: []
paths:
  /v3/global/altcoin-index:
    get:
      tags:
        - Global
      summary: Altcoin Season Index
      description: >-
        **Description**


        Returns the current and previous Altcoin Season Index values with their
        classification.


        > **Note:** Index ≥ 75 - Altcoin Season; 26–74 - Neutral; ≤ 25 - Bitcoin
        Season.


        **Access**

        - Available from: **Sandbox**

        - Cost: 1 credit per request
      operationId: GlobalController_getAltcoinIndex
      parameters: []
      responses:
        '200':
          description: ''
          content:
            application/json:
              schema:
                type: object
                required:
                  - data
                  - status
                properties:
                  data:
                    $ref: '#/components/schemas/GlobalAltcoinIndexResponseDto'
                  status:
                    $ref: '#/components/schemas/ResponseStatusDto'
        '400':
          description: Request validation failed
          content:
            application/json:
              schema:
                type: object
                required:
                  - error
                properties:
                  error:
                    type: object
                    required:
                      - code
                      - message
                      - status
                    properties:
                      code:
                        type: string
                        enum:
                          - VALIDATION_ERROR
                        example: VALIDATION_ERROR
                      message:
                        type: string
                        example: Validation failed
                      status:
                        type: number
                        example: 400
        '401':
          description: API key is missing or invalid
          content:
            application/json:
              schema:
                type: object
                required:
                  - error
                properties:
                  error:
                    type: object
                    required:
                      - code
                      - message
                      - status
                    properties:
                      code:
                        type: string
                        enum:
                          - API_KEY_MISSING
                          - API_KEY_INVALID
                        example: API_KEY_MISSING
                      message:
                        type: string
                        example: API key is missing
                      status:
                        type: number
                        example: 401
        '403':
          description: >-
            No active subscription, the endpoint is not available in your plan,
            or the request goes beyond what your plan allows
          content:
            application/json:
              schema:
                type: object
                required:
                  - error
                properties:
                  error:
                    type: object
                    required:
                      - code
                      - message
                      - status
                    properties:
                      code:
                        type: string
                        enum:
                          - NO_ACTIVE_SUBSCRIPTION
                          - ENDPOINT_NOT_AVAILABLE
                          - PLAN_LIMIT_EXCEEDED
                        example: NO_ACTIVE_SUBSCRIPTION
                      message:
                        type: string
                        example: No active subscription found
                      status:
                        type: number
                        example: 403
        '429':
          description: Rate limit or credit limit exceeded
          content:
            application/json:
              schema:
                type: object
                required:
                  - error
                properties:
                  error:
                    type: object
                    required:
                      - code
                      - message
                      - status
                    properties:
                      code:
                        type: string
                        enum:
                          - RATE_LIMIT_EXCEEDED
                          - DAILY_CREDITS_EXCEEDED
                          - MONTHLY_CREDITS_EXCEEDED
                        example: RATE_LIMIT_EXCEEDED
                      message:
                        type: string
                        example: Rate limit exceeded
                      status:
                        type: number
                        example: 429
        '500':
          description: Internal server error
          content:
            application/json:
              schema:
                type: object
                required:
                  - error
                properties:
                  error:
                    type: object
                    required:
                      - code
                      - message
                      - status
                    properties:
                      code:
                        type: string
                        enum:
                          - INTERNAL_ERROR
                        example: INTERNAL_ERROR
                      message:
                        type: string
                        example: Internal server error
                      status:
                        type: number
                        example: 500
      security:
        - X-Api-Key: []
components:
  schemas:
    GlobalAltcoinIndexResponseDto:
      type: object
      properties:
        currentValue:
          type: number
          example: 71
          description: Current value, 0–100
        classification:
          type: string
          enum:
            - Bitcoin Season
            - Neutral
            - Altcoin Season
          example: Altcoin Season
          description: >-
            Classification by value: Bitcoin Season (≤25), Neutral (26–74),
            Altcoin Season (≥75)
        yesterdayValue:
          type: number
          example: 68
          nullable: true
          description: Value 1 day ago, 0–100
        lastWeekValue:
          type: number
          example: 55
          nullable: true
          description: Value 7 days ago, 0–100
        lastMonthValue:
          type: number
          example: 42
          nullable: true
          description: Value 30 days ago, 0–100
        yearlyHighValue:
          type: number
          example: 89
          description: Highest value over the last year, 0–100
        yearlyHighDate:
          type: string
          example: '2025-11-15T00:00:00.000Z'
          description: Date of the yearly high. ISO 8601
        yearlyLowValue:
          type: number
          example: 12
          description: Lowest value over the last year, 0–100
        yearlyLowDate:
          type: string
          example: '2025-03-10T00:00:00.000Z'
          description: Date of the yearly low. ISO 8601
      required:
        - currentValue
        - classification
        - yesterdayValue
        - lastWeekValue
        - lastMonthValue
        - yearlyHighValue
        - yearlyHighDate
        - yearlyLowValue
        - yearlyLowDate
    ResponseStatusDto:
      type: object
      properties:
        usedCredits:
          type: number
          example: 1
          description: Credits charged for this request
        timestamp:
          type: number
          example: 1780000000000
          description: Server time of the response. Unix timestamp in milliseconds
      required:
        - usedCredits
        - timestamp
  securitySchemes:
    X-Api-Key:
      name: X-Api-Key
      type: apiKey
      in: header

````