Crude Oil VIX (OVX) OHLC Data: How to Retrieve Historical Daily Bars via API

You need historical daily OHLC bars for the Crude Oil VIX (OVX) to power charts, backtests, and risk dashboards. By the end of this guide, you will be able to request OVX daily candles via the OHLC endpoint, verify the latest index print programmatically, and handle practical details like weekends, caching, and date constraints when backfilling series.

What you’re building: reliable OVX daily bars for charts, alerts, and research

Typical jobs include: backfilling a multi-year OVX series for factor research, drawing daily candles on a dashboard, or alerting when the close breaches your volatility threshold. We’ll use two endpoints:

• Latest: to sanity-check live OVX values and your authentication flow.
• OHLC: to retrieve historical daily candles (open, high, low, close) by date.

If you need to iterate over a date range, you can combine these with the time-series endpoint; we’ll cover how to do that safely (including the rule that end_date cannot be today) and how to handle non-trading days.

Symbol, base currency, and units

Indices-API quotes are expressed with a base currency and index symbols. By default, base is USD. For OVX, you’ll see two useful keys under rates:

• OVX: quoted relative to the USD base (USD per one OVX “unit”).
• USDOVX: the reciprocal pair that directly corresponds to the familiar OVX index level.

Always confirm the exact symbol code on the official list before coding. See the reference listing here: Indices-API Supported Symbols. For OVX, the symbol is “OVX.”

Step 1 — Verify your pipeline with the Latest endpoint

Start by confirming that your API key works and your client can parse the schema. This quick call also gives you a live sense-check for OVX before you pull full candles.

curl: get the current OVX print

curl "https://indices-api.com/api/latest?access_key=YOUR_API_KEY"

Example response (copy from your logs to test your parser, then replace YOUR_API_KEY in production). This is an official sample with real fields you’ll see:

{"data":{"success":true,"timestamp":1792125600,"date":"2026-10-16","base":"USD","rates":{"OVX":0.020354162426216,"USD":1,"USDOVX":49.13000000000039}}}

Field mapping you will actually use:

• success: boolean for a successful request.
• timestamp: UNIX epoch seconds. Use it for cache keys and to align downstream updates.
• date: service date in YYYY-MM-DD. Treat this as the market date, not necessarily “now.”
• base: “USD” indicates all rates are quoted relative to USD.
• rates.OVX: the USD-per-OVX quote (reciprocal of the index level).
• rates.USDOVX: the OVX index level equivalent you’ll chart (e.g., about 49.13 in this sample).

Important: For charting or alerts, prefer rates.USDOVX because it matches the conventional index level. If you only have rates.OVX in scope, invert it to get an index-like value; verify numerically with a quick 1 / rates.OVX check against rates.USDOVX.

For complete parameter options and response semantics across endpoints, see the Indices-API Documentation. You can also explore platform capabilities at indices-api.com.

JavaScript fetch example

async function getLatestOVX() {
  const url = "https://indices-api.com/api/latest?access_key=YOUR_API_KEY";
  const res = await fetch(url, { method: "GET" });
  if (!res.ok) throw new Error(`HTTP ${res.status}`);
  const payload = await res.json();

  // Payload shape matches the official sample above
  const { success, timestamp, date, base, rates } = payload.data;

  if (!success) throw new Error("API reported success=false");
  // For charting or UI display, prefer USDOVX
  const ovxLevel = rates.USDOVX; // conventional OVX value
  // For conversions or diagnostics, OVX is the reciprocal
  const ovxReciprocal = rates.OVX; // USD per one OVX

  return {
    timestamp, // UNIX seconds
    date,      // "YYYY-MM-DD"
    base,      // "USD"
    ovxLevel,  // e.g., 49.13...
    ovxReciprocal
  };
}

getLatestOVX()
  .then(console.log)
  .catch(console.error);

Tip: Cache this response keyed by date plus a coarse time bucket; the latest endpoint refresh cadence depends on plan tier (every 60 minutes, 10 minutes, or faster). If your charts only need end-of-day bars, align polling with market close and prefer the OHLC endpoint covered next.

Step 2 — Retrieve historical daily OHLC bars for OVX

Use the OHLC endpoint to fetch canonical open, high, low, and close for a given date. You’ll call it per day to assemble a time series of daily candles suitable for visualization and backtesting.

How the OHLC endpoint works for daily bars

• Path structure: open-high-low-close/YYYY-MM-DD
• Authentication: access_key query parameter
• Response: a rates object keyed by symbol, with an object containing open, high, low, close

For OVX, you’ll request the date you need and read rates.OVX.{open, high, low, close} from the response. Do not fabricate candles; always consume the values returned for that date.

If you need to backfill a long window (e.g., a year of daily bars), iterate dates and call the OHLC endpoint per business day. On weekends and holidays, no OVX bar will be published; skip those days or apply your own calendar logic. If you’re also using the time-series endpoint to discover valid business days across a range, remember that end_date cannot be today—always set it to a completed market date.

For parameter details and examples, see the OHLC section of the Documentation. You can validate the OVX symbol on the Symbols page before coding.

Backfilling a date range safely

When you need N days of OVX candles, the general workflow is:

1. Choose a complete end date (cannot be today) and a start date.
2. Optionally use the time-series endpoint to list dates that have data, or use your own business-day calendar.
3. For each valid date, call the OHLC endpoint and extract rates.OVX.open, .high, .low, .close.
4. Persist results with an idempotent key like symbol+date. Cache raw responses to avoid double billing and speed retries.

Timeouts and retries: OVX consumers often run nightly jobs around settlement time. Add jittered retries and exponential backoff. Because the OHLC endpoint returns one date per request, parallelize modestly and respect your plan’s throughput constraints.

Comparing endpoints you’ll actually use

Data semantics that save you time

• Base and units: base is USD by default. rates.USDOVX is the conventional OVX index value; rates.OVX is its reciprocal (USD per OVX).
• Timestamps: timestamp is UNIX seconds; use UTC consistently in pipelines.
• Trading calendar: OVX is an index derived from options; expect no bar on weekends/holidays. Handle missing dates in your chart gracefully.
• Update cadence: latest refresh frequency depends on your plan (every 60 minutes, 10 minutes, or faster). Align polling with your UX needs.
• Caching: cache raw JSON responses and normalize to your internal schema. Invalidate cache on date change or when timestamp advances.
• Date constraints: for time-series, end_date cannot be today; set it to the latest completed market date.

Putting it together in a small workflow

Here’s a minimal approach to build a daily OVX chart:

1. On first load, request the latest endpoint to display the current OVX level (rates.USDOVX).
2. Backfill the last 90 business days by iterating dates and calling the OHLC endpoint for each date to collect open, high, low, close.
3. Persist candles to your datastore keyed by date. Display the candles on your frontend chart. For today’s provisional bar, you can still show the latest OVX level until the official close is available via OHLC.

If you need to orchestrate at scale, review the managed compute patterns described here: Indices-API MCP. General platform entry point: indices-api.com.

Plan, pricing, and access

Authentication is via an access_key query parameter. PRO is $49.99/mo with a 7-day trial. Get your key and start hitting endpoints in under a minute:

Register

Additional references for OVX users

• Cboe OVX overview for conceptual background on methodology and interpretation.
• Indices-API Documentation for endpoint details and parameters.
• Indices-API Supported Symbols to confirm “OVX” and related tickers before productionizing.

FAQ

Does the OHLC endpoint return partial intraday candles?
No. Use the OHLC endpoint for completed daily bars. For intraday snapshots, rely on the latest endpoint. If you need interval candles, review the intraday endpoint in the Documentation.

Why do I see both OVX and USDOVX in latest?
The base is USD. rates.OVX represents USD per one OVX unit (the reciprocal), while rates.USDOVX directly matches the index level traders typically quote. For charting, use rates.USDOVX.

What happens on weekends and market holidays?
OVX does not publish a daily bar on non-trading days. When iterating dates for OHLC, skip weekends/holidays or pre-compute a business-day calendar. Don’t expect an OHLC object for those dates.

Time-series range rules I should know?
Set end_date to a completed market date—end_date cannot be today. If you need “today so far,” combine your last completed OHLC with the latest endpoint for a provisional level.

How should I cache?
Cache raw JSON by endpoint and parameters. For latest, invalidate on timestamp change. For OHLC, responses are immutable—cache indefinitely and revalidate only if your backfill policy requires audits.

Ready to pull OVX daily bars and ship your chart? Create your API key now and start with the latest sanity check, then move on to OHLC for historical candles: Register.