---
title: "Pairwise Correlation Matrix (CORRMATRIX)"
method: POST
path: "/api/v1/indicators/corrmatrix"
tags: ["Technical Indicators"]
---

# Pairwise Correlation Matrix (CORRMATRIX)

`POST /api/v1/indicators/corrmatrix`

NxN pairwise Pearson correlation of LOG returns of CLOSE prices over the last `window` common trading days (inner-joined on shared dates). Symbols are deduplicated (case-insensitive) and SORTED; since the matrix is symmetric, the response `symbols` and `matrix` keys are in sorted order (this also avoids cache fragmentation). A `null` matrix entry means the pair is undefined (zero-variance series). Daily only (interval=1d). Uses CLOSE prices, matching the close-based BETA / CORREL indicator family.

## Request body

- CorrMatrixRequest — POST body for /api/v1/indicators/corrmatrix.
  - `symbols` string[], required — Tickers to correlate (2-10). Deduplicated (case-insensitive) and sorted; the response `symbols` reflects the sorted-canonical order.
  - `window` integer — Number of most recent common trading days (log-return bars) to correlate over.
  - `interval` string — OHLC interval. Only `1d` is supported (common-trading-days alignment is daily-only).
  - `range` string, nullable — Optional range string for the underlying OHLC fetch (e.g. `1y`, `2y`).

## Response `200`

Successful Response

- EnvelopeCorrMatrixPayload
  - `data` CorrMatrixPayload, required — NxN pairwise Pearson correlation of log returns over the common window.
    - `symbols` string[], required — Sorted-canonical list of unique symbols actually correlated.
    - `interval` string, required — OHLC interval used. Always `1d`.
    - `window` integer, required — Requested correlation window (bars).
    - `common_bars` integer, required — Number of common log-return bars used (after inner-join + dropna, capped at `window`).
    - `matrix` object, required — Nested NxN correlation matrix keyed by symbol. Diagonal is 1.0. A `null` entry means the pair is undefined (zero-variance series).
    - `source` string — OHLC data source used. Currently always `sugra_finance`.
  - `meta` SugraMeta, required — Metadata attached to every /api/v1/* response envelope.
    - `endpoint` string, required — Requested endpoint path.
    - `data_time` string, required — ISO 8601 UTC timestamp of the source data, not of the request.
    - `response_time` string, required — ISO 8601 UTC timestamp when this response was produced.
    - `provider` string, required — API name and version.
    - `source` string, nullable — Identifier of the primary upstream source used for this response.
    - `attribution` string, nullable — Human-readable attribution mandated by an upstream source (e.g. a securities regulator or self-regulatory organization). Present only on responses whose source requires the owner and source to be clearly identified. Do not remove or alter it when using the response.
    - `fallback_used` boolean, nullable — True when the primary source failed and a fallback produced the data.
    - `fallback_chain` string[], nullable — Ordered list of sources attempted, in the order they were tried.
    - `cached` boolean, nullable — True when this response was served from the internal cache.
    - `stale` boolean, nullable — True when the cached response was returned after the upstream rate-limited or errored. Clients can use this to detect degraded data.

## Other responses

- `401` — Missing or invalid `x-api-key` header. JSON body with a stable `code` distinguishing `missing_api_key` (no header sent) from `invalid_api_key` (header sent, key not accepted); any other 401 source carries the generic `unauthorized` with its detail as `reason`. Plus `hint`. `plan` is always null on 401 - an unauthenticated request has no plan; quota exhaustion is 429, not 401.
- `422` — Validation Error
- `429` — Daily rate limit exceeded. Check `X-RateLimit-Reset` for the next window.
- `503` — Upstream source is temporarily unavailable. Retry after a short delay.

## Changes

- **2026-08-08** `4c4530760ba1` — 12 info
  - added the optional property `code` to the response with the `401` status
  - added the optional property `code` to the response with the `429` status
  - added the optional property `code` to the response with the `503` status
  - added the optional property `hint` to the response with the `401` status
  - …8 more

[Change history](https://skmtc.dev/sugra/apis/sugra-api/changes/api/v1/indicators/corrmatrix/post.md)

---

[API](https://skmtc.dev/sugra/apis/sugra-api.md) · [All operations](https://skmtc.dev/sugra/apis/sugra-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/sugra/sugra-api/revisions/87582f2e0110/schema)