> ## 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.

# Multi-symbol bundling

> Get the universe in one round-trip via /v2/multi/gex/levels

Desk dashboards routinely watch the entire crypto-options universe at
once: BTC + ETH + SOL + HYPE. Hitting `/v2/gex/levels` four times means
four HTTP round-trips. The multi endpoint collapses that into one.

## The endpoint

[`/v2/multi/gex/levels`](/api/v2/multi/gex-levels) takes a CSV of
symbols (up to 8) and returns a `results` map keyed by symbol:

```bash theme={null}
curl "https://api.backquant.com/v2/multi/gex/levels?\
symbols=BTCUSDT,ETHUSDT,SOLUSDT,HYPEUSDT\
&include=ranked,max_pain,expected_move,zones" \
  -H "X-API-Key: YOUR_API_KEY"
```

```json theme={null}
{
  "results": {
    "BTCUSDT": {
      "all_expiry": { "hvl": 67000, "call_resistance": 70000, ... },
      "odte": { "hvl": 67500, ... },
      "spot_price": 67213.5,
      "computed_at": "2026-04-30T11:59:48Z",
      "ranked": { "all_expiry_top_10": [...], "odte_top_10": [...] },
      "max_pain": { "strike": 67500, "value": 5e7 },
      "expected_move": { "upper_1sd": 70000, "lower_1sd": 64000, ... }
    },
    "ETHUSDT": { ... },
    "SOLUSDT": { ... },
    "HYPEUSDT": { ... }
  },
  "requested": ["BTCUSDT", "ETHUSDT", "SOLUSDT", "HYPEUSDT"],
  "served": ["BTCUSDT", "ETHUSDT", "SOLUSDT", "HYPEUSDT"],
  "missing": [],
  "invalid": []
}
```

## Why it's faster than N calls

Server-side, the bundle endpoint batches every lookup into a single
operation rather than serving them sequentially. The result: one HTTP
round-trip instead of N, and lower upstream load on our side.

For a desk dashboard polling on a 30s loop, that's a 4× reduction in
round-trips with no client-side change beyond switching to the bundle
endpoint.

## Partial results

If one of the requested symbols has no live data (cold cache), it
appears in `missing` and its `results[symbol]` is `null` — but the
other symbols still come back. **The whole call doesn't fail** because
of one stale symbol.

```json theme={null}
{
  "results": {
    "BTCUSDT": { ... },
    "ETHUSDT": { ... },
    "SOLUSDT": null,
    "HYPEUSDT": { ... }
  },
  "requested": ["BTCUSDT", "ETHUSDT", "SOLUSDT", "HYPEUSDT"],
  "served": ["BTCUSDT", "ETHUSDT", "HYPEUSDT"],
  "missing": ["SOLUSDT"],
  "invalid": []
}
```

`invalid` lists symbols that aren't in the supported set
(BTCUSDT/ETHUSDT/SOLUSDT/HYPEUSDT) — your client got the symbol name
wrong.

## Filters

* `?exchanges=deribit,bybit,okx,binance` — same venue filter as
  single-symbol; applies to every symbol in the bundle.
* `?include=ranked,max_pain,expected_move,zones` — same composable
  includes. The single-symbol `spot` and `candles` includes are
  intentionally absent here to keep the bundled payload bounded
  (candles arrays would multiply payload by \~10×).

## Limits

* **Up to 8 symbols** per request (you have 4 today; the cap leaves
  room for future expansion).
* Duplicate symbols in the request are de-duplicated while preserving
  caller order.

## When to use it

**Use it for**: dashboard refreshes, multi-symbol overlays, screeners
that scan the universe.

**Don't use it for**: single-symbol drilldowns. The per-symbol
endpoints support more includes (`spot`, `candles`) that the multi
endpoint omits.

## Related concepts

<CardGroup cols={2}>
  <Card title="What is GEX?" icon="chart-line" href="/concepts/gex">
    The data this bundles is the same as `/v2/gex/levels` per symbol.
  </Card>

  <Card title="Data freshness" icon="bolt" href="/concepts/data-freshness">
    The shared cache that makes the bundle cheap.
  </Card>
</CardGroup>