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

# Order Book

> Retrieve real-time order book depth (bids & asks) for a trading symbol.

## Notes

* bids sorted by price descending
* asks sorted by price ascending
* timestamp in milliseconds (UTC)

## Supported Markets

**US Stocks**, **HK Stocks**, **A-Shares**, **China Futures**, **Crypto**

Examples:

* US Stocks: AAPL.US, TSLA.US, MSFT.US
* HK Stocks: 700.HK, 9988.HK, 3690.HK
* A-Shares: 600519.SH, 000001.SZ, 920186.BJ
* China Futures: BU2609, IC2606, AP8888
* Crypto: BTCUSDT, ETHUSDT, ADAUSDT

## Request Parameters

| Parameter | Required | Description                                                                                                                                                                                               |
| --------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| symbol    | Yes      | Trading symbol code                                                                                                                                                                                       |
| limit     | No       | Depth levels, default 10, max 50                                                                                                                                                                          |
| type      | No       | Symbol type, optional. Not required when the symbol is unambiguous; if the API returns an `AMBIGUOUS_SYMBOL` error, pass the value as indicated. Values: `stock`, `indices`, `crypto`, `forex`, `futures` |

## Response Fields

| Field     | Description                                   |
| --------- | --------------------------------------------- |
| symbol    | Trading Symbol                                |
| type      | Product type                                  |
| timestamp | Data timestamp (milliseconds, UTC)            |
| bids      | Bid array, each element is \[price, quantity] |
| asks      | Ask array, each element is \[price, quantity] |


## OpenAPI

````yaml GET /v1/market/depth
openapi: 3.0.0
info:
  title: TickDB API
  description: >-
    Unified real-time market data API — one connection for Forex, indices, US
    stocks, HK stocks, A-shares, China futures, and Crypto via REST and
    WebSocket.
  version: 1.0.2
  contact:
    email: support@tickdb.ai
servers:
  - url: https://api.tickdb.ai
    description: Production server
security:
  - ApiKeyAuth: []
paths:
  /v1/market/depth:
    get:
      summary: Order Book
      description: Get real-time order book bids and asks
      parameters:
        - name: symbol
          in: query
          required: true
          description: Trading symbol
          schema:
            type: string
            default: 700.HK
            example: 700.HK
        - name: limit
          in: query
          required: false
          description: Depth levels (default 10, max 50)
          schema:
            type: integer
            minimum: 1
            maximum: 50
            example: 20
        - name: type
          in: query
          required: false
          description: >-
            Symbol type, optional. Not required when the symbol is unambiguous;
            if the API returns an AMBIGUOUS_SYMBOL error, pass the value as
            indicated
          schema:
            type: string
            enum:
              - stock
              - indices
              - crypto
              - forex
              - futures
            example: stock
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                type: object
                properties:
                  code:
                    type: integer
                    example: 0
                  message:
                    type: string
                    example: success
                  data:
                    type: object
                    properties:
                      symbol:
                        type: string
                        example: 700.HK
                      type:
                        type: string
                        enum:
                          - stock
                          - indices
                          - crypto
                          - forex
                          - futures
                      timestamp:
                        type: integer
                        example: 1768274016162
                      bids:
                        type: array
                        description: Buy orders sorted by price descending
                        items:
                          type: array
                          items:
                            type: string
                        example:
                          - - '626'
                            - '19700'
                          - - '625.5'
                            - '40800'
                      asks:
                        type: array
                        description: Sell orders sorted by price ascending
                        items:
                          type: array
                          items:
                            type: string
                        example:
                          - - '626.5'
                            - '36100'
                          - - '627'
                            - '50700'
components:
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key

````