> ## Documentation Index > Fetch the complete documentation index at: https://docs.backquant.com/llms.txt > Use this file to discover all available pages before exploring further. # Strike ladder > Dealer exposure by strike and expiry for every greek, and the dealer position in contracts. The grid behind the terminal's HEATMAP: one metric per call (`gex`, `dex`, `vanna`, `charm`, `vega`, `oi` or `pos`), with a row per strike and a column per expiry, plus each strike's total over every expiry in scope. `pos` is the dealer position itself, in contracts: where dealers are longest and shortest, by strike and by expiry. With `positioning=flow` (the default for BTC and ETH) it is measured from the tape; see [How flow is measured](/concepts/positioning#how-flow-is-measured). ```bash theme={null} curl -H "X-API-Key: $KEY" \ "https://api.backquant.com/v2/gex/ladder?symbol=BTCUSDT&metric=pos&expiry=week" ``` `expiry` takes `all`, `0dte`, `front`, `week`, `month`, ISO dates or tokens such as `30OCT26`. Every expiry in the response carries both forms. ## See also ## OpenAPI ````yaml GET /gex/ladder openapi: 3.1.0 info: title: BackQuant API v2 description: >- # BackQuant API v2 Options + gamma-exposure focused public API. Built on the same data the BackQuant Pro Terminal renders - pre-computed every 30s, served from cache. ## What's in v2 * **Discovery**: `/v2/symbols` (universe + per-symbol freshness + supported endpoint list), `/v2/expiries` (active expiry tokens with DTE), `/v2/status` (per-symbol-per-category health with thresholds + overall classification). * **GEX**: composable levels (HVL / call wall / put support / max-pain / expected move / gamma-flip zones), strike profile with typed expiry filter, expiry profile, strike × expiry heatmap with downsampling, greek time-heatmap with DTE/OI/IV filters, history (cursor-paginated), Postgres-backed stress history, **per-expiry max-pain with pain curve**. * **Options**: filtered options chain with two-layer projection (top-level `?fields=` and per-contract `?include=oi,iv,greeks,bid_ask,volume,gex`) plus moneyness filter (`?moneyness_min=0.9&moneyness_max=1.1`), expiry summary table, full IV suite (surface / term structure / 25Δ-10Δ skew / curves / **single-expiry smile** / IV-RV history / VRP), expected move, **Breeden-Litzenberger probability density and surface**, typed greek profiles (delta / theta / vanna / charm / vega), strike × time charm/vega surfaces, strike × expiry 3D greek surface, OI by expiry + history, put/call ratio (intraday or daily), 0DTE & weekly premium tide, dated-futures term structure. * **Liquidation**: heatmap + leverage-tiered distribution. * **Multi**: `/v2/multi/gex/levels` - bundled multi-symbol read across the universe in one round-trip, with the same `?include=` model as the single-symbol endpoint. ## Authentication Every v2 route (except `/v2/openapi.json`, `/v2/docs`, `/v2/redoc`, and `/v2/health`) requires the `X-API-Key` header. ``` X-API-Key: bq_live_your_api_key_here ``` **Get your API key at [backquant.com/api-access](https://backquant.com/api-access).** The same key works across v1 and v2 - if you already have a v1 key, no re-issuance is needed. ## Rate limits Two budgets, both derived from your subscription tier: a **monthly request allowance** per account, and a **per-minute burst** per key. Size your integration against the monthly figure - sustained polling at the burst rate exhausts the month early. | Plan | Monthly allowance | Burst | Sustained | |---------------------------|-------------------|----------|-------------| | Starter (Terminal Yearly) | 10,000 req/month | 10/min | ~333/day | | Standard (Crypto API) | 250,000 req/month | 60/min | ~8,300/day | | Pro (Terminal + API) | 1,000,000/month | 120/min | ~33,000/day | | Enterprise | custom | 600/min | custom | Headers `X-RateLimit-Limit / -Remaining / -Reset` (burst) and `X-Quota-Limit / -Used / -Remaining / -Period` (monthly) are included in every response; the rate-limit triple is echoed inside `meta.rate_limit` when populated by middleware. Exceeding either budget returns `429`. The live ladder is served at `GET /v2/meta` under `rate_limits`. ## Response envelope ```json { "success": true, "data": { ... }, "meta": { "version": "2.0", "timestamp": "2026-04-29T12:00:00.000Z", "request_id": "req_…", "symbol": "BTCUSDT", "spot_price": 67213.5, "computed_at": "2026-04-29T11:59:48.000Z", "freshness_seconds": 12.0, "source": ["deribit","bybit","okx","binance","derive","thalex","delta_india","delta","bullish","paradex"], "exchanges_filtered": ["deribit","bybit"] } } ``` ## Errors ```json { "success": false, "error": { "code": "NOT_FOUND", "message": "No data for BTCUSDT" }, "meta": { "version": "2.0", "timestamp": "..." } } ``` | Code | When | |-----------------------|------| | `UNAUTHORIZED` | Missing or invalid API key | | `FORBIDDEN` | Subscription doesn't allow API access | | `NOT_FOUND` | Symbol/expiry/etc. not present in cache | | `VALIDATION_ERROR` | Bad query parameters | | `RATE_LIMIT_EXCEEDED` | Per-tier limit hit | | `UPSTREAM_ERROR` | Cache or DB temporarily unreachable | | `INTERNAL_ERROR` | Anything else | version: '2.13' servers: [] security: [] tags: - name: Meta description: Unauthenticated metadata + endpoint catalog (planning your integration) - name: Discovery description: Symbol catalog, active expiries, and service status - name: GEX description: Gamma exposure analytics - name: Options description: Options chain, IV, greeks, probability, premium tide - name: Liquidation description: Liquidation heatmap and distribution - name: Multi description: Bundled multi-symbol endpoints (single round-trip across the universe) - name: COT description: >- CFTC Commitments of Traders: futures positioning by trader category (public CFTC data) - name: Filings description: >- SEC Form 4 insider trades and 13F holders for MSTR, COIN, HOOD and IBIT (public SEC data) paths: /gex/ladder: get: tags: - GEX summary: 'Strike ladder: dealer exposure by strike x expiry' description: >- Dealer exposure per strike and per expiry for one metric, the grid behind the terminal's HEATMAP. Every value is dealer position x greek per contract, summed per (strike, expiry): * `gex` - $ of delta dealers must trade per 1% move * `dex` - $ delta * `vanna` - $ of delta per +1 vol point * `charm` - $ of delta per day of time passing * `vega` - $ per +1 vol point * `oi` - open interest in contracts (unsigned) * `pos` - the dealer position itself, in contracts `cells` has one row per strike in `strikes` and one column per expiry in `expiries` (the nearest `expiries`, default 8). `total` is each strike summed over every expiry in scope, including those beyond the columns, and `top` / `king` rank strikes by it. For `gex`, `levels` carries the gamma flip and walls by the same rule as /v2/gex/levels. **Positioning (default: flow).** `flow` uses BackQuant's measured dealer position (BTC and ETH); `std` the textbook convention (call:+OI, put:-OI). See `meta.extra.positioning`; `oi` is unsigned. `expiry` scopes which expiries count: `all`, `0dte`, `front`, `week` (7 days), `month` (31 days), or a comma list of ISO dates or tokens like `30OCT26`. `span` keeps strikes within spot x (1 +/- span); `group` merges strikes into buckets about that many strike steps wide. Every venue in the chain is included. operationId: get_gex_ladder_gex_ladder_get parameters: - name: symbol in: query required: false schema: enum: - BTCUSDT - ETHUSDT - SOLUSDT - HYPEUSDT type: string description: 'Trading symbol: BTCUSDT, ETHUSDT, SOLUSDT, or HYPEUSDT.' default: BTCUSDT title: Symbol description: 'Trading symbol: BTCUSDT, ETHUSDT, SOLUSDT, or HYPEUSDT.' - name: metric in: query required: false schema: enum: - gex - dex - vanna - charm - vega - oi - pos type: string description: 'Which exposure: gex, dex, vanna, charm, vega, oi or pos.' default: gex title: Metric description: 'Which exposure: gex, dex, vanna, charm, vega, oi or pos.' - name: positioning in: query required: false schema: anyOf: - type: string - type: 'null' description: >- Dealer positioning model. **`flow`** (default) is BackQuant's measured dealer model, available for BTC/ETH; it falls back to `std` when it cannot be produced for a symbol. **`std`** is the textbook convention (call:+OI / put:-OI). The response reports which model actually ran in `meta.extra.positioning`. default: flow title: Positioning description: >- Dealer positioning model. **`flow`** (default) is BackQuant's measured dealer model, available for BTC/ETH; it falls back to `std` when it cannot be produced for a symbol. **`std`** is the textbook convention (call:+OI / put:-OI). The response reports which model actually ran in `meta.extra.positioning`. - name: expiry in: query required: false schema: type: string maxLength: 400 description: >- all, 0dte, front, week, month, or a comma list of ISO dates / tokens (30OCT26). default: all title: Expiry description: >- all, 0dte, front, week, month, or a comma list of ISO dates / tokens (30OCT26). - name: expiries in: query required: false schema: type: integer maximum: 24 minimum: 0 description: How many of the nearest expiries get their own column. default: 8 title: Expiries description: How many of the nearest expiries get their own column. - name: span in: query required: false schema: anyOf: - type: number maximum: 0.5 minimum: 0.005 - type: 'null' description: Strikes within spot x (1 +/- span). Default 0.12. title: Span description: Strikes within spot x (1 +/- span). Default 0.12. - name: group in: query required: false schema: type: integer maximum: 20 minimum: 1 description: Merge strikes into buckets about this many strike steps wide. default: 1 title: Group description: Merge strikes into buckets about this many strike steps wide. - name: X-API-Key in: header required: false schema: anyOf: - type: string - type: 'null' title: X-Api-Key responses: '200': description: Successful Response content: application/json: schema: {} '401': description: Invalid or missing API key content: application/json: example: success: false error: code: UNAUTHORIZED message: Invalid API key meta: version: '2.0' timestamp: '2026-04-29T12:00:00Z' '404': description: No data available for the requested resource content: application/json: example: success: false error: code: NOT_FOUND message: No data for BTCUSDT meta: version: '2.0' timestamp: '2026-04-29T12:00:00Z' '422': description: Validation error on query parameters content: application/json: example: success: false error: code: VALIDATION_ERROR message: Invalid request parameters details: errors: [] meta: version: '2.0' timestamp: '2026-04-29T12:00:00Z' '429': description: Rate limit exceeded content: application/json: example: success: false error: code: RATE_LIMIT_EXCEEDED message: Rate limit exceeded. Try again later. meta: version: '2.0' timestamp: '2026-04-29T12:00:00Z' security: - ApiKeyAuth: [] components: securitySchemes: ApiKeyAuth: type: apiKey in: header name: X-API-Key description: Your BackQuant API key (same key as v1) ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.