Get BTC Volatility History (RV + ATR%)
arena_get_volatility_historyHow volatile has Bitcoin been? Daily Bitcoin volatility time series: realized volatility (30d & 90d, √252-annualized, close-to-close) and ATR% (Wilder EMA-14, captures intraday range + gaps), on the same scale. Ranks come in two flavours answering different questions: rvRank/atrPctAnnRank expand from the start of history and are look-ahead-free, but they include BTC's structural volatility decline; rvRankRolling/atrPctAnnRankRolling rank against a trailing 2-year window, which removes that trend from the comparison. History reaches back to 2009 via a stitched pre-Binance close series; ATR is null before the Binance era because no daily high/low exists that far back (see meta.coverage). Use from/to for a specific window instead of pulling everything and discarding it, and granularity/fields to keep long ranges affordable. For long ranges pass schema_version: "2026-08" (rounds floats; opt-in until the default flips 2026-11-01) plus fields: "minimal" and meta: "minimal" — every response carries a size block with chars_before/chars_after/saved_pct measuring the saving for YOUR call. Free tier: last 365 days. Related: arena_get_volatility_phases (current phase per pair), arena_get_iv_snapshot (implied vs. this realized — same RV method, but its realized_vol_30d is computed at snapshot time BEFORE that date has traded, so on fresh breakout days the two can differ; this series uses completed closes and is the one to trust for finished days), arena_get_cycle (regime context). [Free tier]
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| to | No | ISO date (YYYY-MM-DD), inclusive. End of the window. Defaults to the latest bar. | |
| days | No | Number of most recent days to return. Free tier capped at 365; API Pro unlimited. Ignored when from/to are given. | |
| from | No | ISO date (YYYY-MM-DD), inclusive. Start of the window. Free tier still only sees the last 365 days. | |
| meta | No | Default full. 'minimal' drops params/params_hash/warmup, which are only useful on the first call. | |
| fields | No | Default full. 'minimal' returns date, close, rv, rvRank, rvRankRolling, atrPctAnnRank, atrPctAnnRankRolling only — measured saving 18–20 % of characters (full-history series, 2026-07-31; the `size` block in the response has the figure for your actual call), not a fifth of the size. Combine with granularity or a from/to window for a real reduction; dropping fields alone saves less than it looks. | |
| granularity | No | Default daily. weekly/monthly keep the LAST observation of each period (a state, not an average). | |
| schema_version | No | Default '2026-07' (unchanged output). '2026-08' rounds floats to 2 decimals (ranks 1) and reports the saving. Default flips 2026-11-01. |