Bitcoin RSI chart: the 22-day Relative Strength Index on daily closes, with the 30 / 70 reference levels and the 80 reading that marked previous cycle peaks. Full history since 2010, updated daily.
Left axis: BTC price (log). Right axis: Wilder RSI with a 22-day period on daily closes (0–100).
RSI = 100 − 100 / (1 + average gain / average loss), Wilder smoothing, 22-day period on daily closes
The Relative Strength Index compares the size of recent up-days with recent down-days. Coinfuty uses Wilder's original smoothing with a 22-day period — roughly one trading month — on the daily close, computed over the full history from 2010 so no seed-window artefacts remain. Readings above 70 are conventionally overbought, below 30 oversold.
On a daily 22-period basis, Bitcoin's cycle tops in 2013, 2017 and 2021 all printed RSI above 80, and the strongest impulses reached the high 80s. Readings above 80 do not time the top — they can persist for weeks in a parabolic advance — but every major top occurred while RSI was in that zone. Oversold readings below 30 have coincided with capitulation lows.
70.6 on the daily 22-day RSI as of Sep 4, 2026 — overbought, above 70.
The conventional level is 70, but Bitcoin's strongest advances spend weeks above it. The 80 reading used here filters for the parabolic phase: the 2013, 2017 and 2021 cycle tops all occurred with the daily 22-period RSI above 80.
22 trading days is roughly a month, which smooths the day-to-day noise of the 14-period version and makes the indicator better at distinguishing cycle extremes from routine swings. Both use Wilder's smoothing.
As a momentum gauge, yes: extremes have lined up with major tops and bottoms. As a timing tool, no — RSI can stay above 80 for weeks, so use it as a condition for a top, not a trigger.
Coinfuty computes every series on this page from daily BTC close prices and public constants — the Bitcoin halving schedule, block subsidy and published regression coefficients. Values refresh nightly (00:20 UTC) and the current day is patched hourly. These are historical, backward-looking indicators; nothing here is investment advice.