Bavest QuantOS

QuantOS Portfolio Return

POST/v2/quant-os/return

Calculate portfolio return over a specified period.

Included in: Growth.

Authentication

Send your API key in the x-api-key header on every request to https://api.bavest.co. The samples read it from the BAVEST_API_KEY environment variable. Get an API key · Authentication guide

Parameters

This route takes no path or query parameters.

Try it

JSON body

Draft from the schema. Review and fill in required fields before sending.

POST /v2/quant-os/return

API key

Sent only to api.bavest.co for this request; not stored.

Sign in to send Get an API keySends with the key above, or sign in to use your account's key. Each request counts as one API call.

curl -X POST 'https://api.bavest.co/v2/quant-os/return' \
  -H "x-api-key: $BAVEST_API_KEY" \
  -H 'content-type: application/json' \
  --data '{"portfolioItems":[{"symbol":"AAPL","weight":0.4,"buyDate":"2026-09-01"},{"symbol":"MSFT","weight":0.35,"buyDate":"2026-09-01"},{"symbol":"GOOGL","weight":0.25,"buyDate":"2026-09-01"}],"startDate":"2026-09-01","endDate":"2026-11-13","currency":"USD","resolution":"D"}'

Samples read your key from BAVEST_API_KEY and follow the form.

Example response 200

{
  "data": {
    "beta": 0,
    "performanceSixMonths": 15.7361,
    "performanceOneWeek": 0.2813,
    "performanceOneYear": 13.9087,
    "dividendPerShareAnnual": 0
  },
  "meta": {
    "parameters": {
      "startDate": "2026-09-01",
      "endDate": "2026-09-30",
      "currency": "USD",
      "resolution": "D",
      "portfolio_items": [
        {
          "symbol": "AAPL",
          "weight": 0.4,
          "buy_date": 1788220800000
        },
        {
          "symbol": "MSFT",
          "weight": 0.35,
          "buy_date": 1788220800000
        },
        {
          "symbol": "GOOGL",
          "weight": 0.25,
          "buy_date": 1788220800000
        }
      ],
      "from": 1788220800,
      "to": 1790726400
    },
    "time": 7337
  }
}

From the docs, not your data. Long lists are cut to 3 items.

Request body

Symbols, weights, and date range for analysis.

portfolioItemsarray of objectrequired
Portfolio positions with symbol, allocation weight, and purchase date
- symbolstringrequired
  Ticker symbol
  Example AAPL
- weightnumberrequired
  Allocation weight (all weights must sum to 1.0)
  Example 0.4
- buyDatestring (date)required
  Purchase date (YYYY-MM-DD). Converted to Unix timestamp internally.
  Example 2026-09-01
- amountnumber
  Number of shares held
startDatestring (date)
Analysis start date (YYYY-MM-DD)
Example 2026-09-01
endDatestring (date)
Analysis end date (YYYY-MM-DD)
Example 2026-09-30
currencystring
Target currency for valuation (ISO 4217)
Example USD
resolutionstring
Data resolution for time series
One of D W M
Example D

Response 200

Successful response · application/json

dataQuantOSReturn
Portfolio return calculation.
- totalReturnnumber (double)
  Cumulative return over period (decimal)
- annualizedReturnnumber (double)
  Annualized return (decimal)
- betanumber (double)
  Portfolio beta
  Example 0
- dividendPerShareAnnualnumber (double)
  Annual dividend per share (USD)
  Example 0
- performanceOneWeeknumber (double)
  One-week return
  Example 0
- performanceOneYearnumber (double)
  One-year return
  Example 0
- performanceSixMonthsnumber (double)
  Six-month return
  Example 0
metaResponseMeta
Response envelope metadata. Always present on a 200: time is set by core/response.py on every successful response. Errors carry the same block, built by the same code, so a client parses one meta shape whether the call succeeded or failed.
- timeinteger
  Server-side processing time in milliseconds
  Example 17
- parametersobject
  Echo of the request parameters the endpoint resolved

Errors

400Invalid request parameters. Returned when required query parameters are missing, have invalid types, or violate constraints (e.g., providing both symbol and isin when they are mutually exclusive).
401Missing or invalid API key.
404Resource not found.
429Rate limit exceeded. Retry after the `Retry-After` header interval.
500An unexpected error occurred on the server. If the issue persists, contact support with the X-Request-Id header value.
502Upstream data provider returned an error or is temporarily unavailable. Retry after a short delay.
504The request timed out waiting for a response from the upstream data provider. This may occur for complex queries or during peak load.
defaultAn unexpected error occurred on the server. If the issue persists, contact support with the X-Request-Id header value.