RSI (14)
What share of the last few days' movement has been to the upside, on a 0-100 scale.
Why it matters
It's technical analysis' best-known oscillator and answers a simple question: of everything price has moved lately, how much was upward? 50 means a tie. The classic reading — above 70 "overbought", below 30 "oversold" — needs care in Bitcoin: in a strong trend RSI can sit above 70 for weeks without that being a sell signal. It measures recent intensity, not exhaustion.
Build it yourself
Start from the already-smoothed average gain and average loss, and watch how they get compressed onto the 0-100 scale.
Notice RSI never reaches 0 or 100 unless one of the two averages is zero: it's a compression, not a linear scale of movement.
Illustrative example numbers for practice — not real data.
How it's calculated, step by step
- For each day the price change against the previous day is computed and split into two series: gains (down days count as 0) and losses as positives (up days count as 0).
- Each series is smoothed with a 14-period exponential average, giving average gain and average loss.
- RS = average gain ÷ average loss. RSI = 100 − 100 ÷ (1 + RS). The first value appears from day 14 onward.
Chart
This is real Bitcoin data, computed from the blockchain — not the illustrative example above.
Data last updated on 2026-09-09.